X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=threads2i.c;fp=threads2i.c;h=25feba3b5ef345f7b97ff78cdf177cbe4835d56e;hb=418c6dcf655db4593f628193de63d486156a72e9;hp=25a26fdfa0cf83c56cb86106b5d95b8ceeceeabf;hpb=eaa1665f4f3d30fe42fae361ff96be82a8515b3e;p=btree diff --git a/threads2i.c b/threads2i.c index 25a26fd..25feba3 100644 --- a/threads2i.c +++ b/threads2i.c @@ -1,5 +1,5 @@ -// btree version threads2i linux futex concurrency version -// 09 JAN 2014 +// btree version threads2i sched_yield version +// 24 JAN 2014 // author: karl malbrain, malbrain@cal.berkeley.edu @@ -25,8 +25,6 @@ REDISTRIBUTION OF THIS SOFTWARE. #ifdef linux #define _GNU_SOURCE -#include -#define SYS_futex 202 #endif #ifdef unix @@ -38,7 +36,6 @@ REDISTRIBUTION OF THIS SOFTWARE. #include #include #include -#include #else #define WIN32_LEAN_AND_MEAN #include @@ -61,6 +58,8 @@ typedef unsigned short ushort; typedef unsigned int uint; #endif +#define BT_latchtable 128 // number of latch manager slots + #define BT_ro 0x6f72 // ro #define BT_rw 0x7772 // rw @@ -89,33 +88,42 @@ typedef enum{ // mode & definition for latch implementation enum { - Mutex = 1 << 0, // the mutex bit - Write = 1 << 1, // the writers bit - Share = 1 << 2, // reader count - PendRd = 1 << 12, // reader contended count - PendWr = 1 << 22 // writer contended count + Mutex = 1, + Write = 2, + Pending = 4, + Share = 8 } LockMode; -enum { - QueRd = 1, // reader queue - QueWr = 2 // writer queue -} RWQueue; - +// exclusive is set for write access // share is count of read accessors // grant write lock when share == 0 typedef struct { - volatile uint mutex:1; // 1 = busy - volatile uint write:1; // 1 = exclusive - volatile uint share:10; // count of readers holding locks - volatile uint readwait:10; // count of readers waiting - volatile uint writewait:10; // count of writers waiting -} BtLatch; + volatile ushort mutex:1; + volatile ushort exclusive:1; + volatile ushort pending:1; + volatile ushort share:13; +} BtSpinLatch; + +// hash table entries + +typedef struct { + BtSpinLatch latch[1]; + volatile ushort slot; // Latch table entry at head of chain +} BtHashEntry; + +// latch manager table structure typedef struct { - BtLatch readwr[1]; // read/write page lock - BtLatch access[1]; // Access Intent/Page delete - BtLatch parent[1]; // Parent modification + BtSpinLatch readwr[1]; // read/write page lock + BtSpinLatch access[1]; // Access Intent/Page delete + BtSpinLatch parent[1]; // adoption of foster children + BtSpinLatch busy[1]; // slot is being moved between chains + volatile ushort next; // next entry in hash table chain + volatile ushort prev; // prev entry in hash table chain + volatile ushort pin; // number of outstanding locks + volatile ushort hash; // hash slot entry is under + volatile uid page_no; // latch set page number } BtLatchSet; // Define the length of the page and key pointers @@ -163,6 +171,7 @@ typedef struct Page { unsigned char kill:1; // page is being deleted unsigned char dirty:1; // page has deleted keys unsigned char right[BtId]; // page number to right + BtSlot table[0]; // array of key slots } *BtPage; // The memory mapping pool table buffer manager entry @@ -171,8 +180,8 @@ typedef struct { unsigned long long int lru; // number of times accessed uid basepage; // mapped base page number char *map; // mapped memory pointer - uint slot; // slot index in this array - volatile uint pin; // mapped page pin counter + ushort slot; // slot index in this array + ushort pin; // mapped page pin counter void *hashprev; // previous pool entry for the same hash idx void *hashnext; // next pool entry for the same hash idx #ifndef unix @@ -180,6 +189,19 @@ typedef struct { #endif } BtPool; +// structure for latch manager on ALLOC_page + +typedef struct { + struct Page alloc[2]; // next & free page_nos in right ptr + BtSpinLatch lock[1]; // allocation area lite latch + ushort latchdeployed; // highest number of latch entries deployed + ushort nlatchpage; // number of latch pages at BT_latch + ushort latchtotal; // number of page latch entries + ushort latchhash; // number of latch hash table slots + ushort latchvictim; // next latch entry to examine + BtHashEntry table[0]; // the hash table +} BtLatchMgr; + // The object structure for Btree access typedef struct { @@ -193,27 +215,33 @@ typedef struct { #else HANDLE idx; #endif - volatile uint poolcnt; // highest page pool node in use + ushort poolcnt; // highest page pool node in use + ushort poolmax; // highest page pool node allocated + ushort poolmask; // total number of pages in mmap segment - 1 + ushort hashsize; // size of Hash Table for pool entries volatile uint evicted; // last evicted hash table slot - uint poolmax; // highest page pool node allocated - uint poolmask; // total size of pages in mmap segment - 1 - uint hashsize; // size of Hash Table for pool entries ushort *hash; // pool index for hash entries - BtLatch *latch; // latches for hash table slots + BtSpinLatch *latch; // latches for hash table slots + BtLatchMgr *latchmgr; // mapped latch page from allocation page + BtLatchSet *latchsets; // mapped latch set from latch pages BtPool *pool; // memory pool page segments +#ifndef unix + HANDLE halloc; // allocation and latch table handle +#endif } BtMgr; typedef struct { BtMgr *mgr; // buffer manager for thread - BtPage temp; // temporary frame buffer (memory mapped/file IO) - BtPage alloc; // frame buffer for alloc page ( mapped to page 0 ) BtPage cursor; // cached frame for start/next (never mapped) BtPage frame; // spare frame for the page split (never mapped) - BtPage zero; // page of zeroes to extend the file (never mapped) - BtPage page; // current page mapped from file + BtPage zero; // page frame for zeroes at end of file + BtPage page; // current page uid page_no; // current page number uid cursor_page; // current cursor page number + BtLatchSet *set; // current page latch set + BtPool *pool; // current page pool unsigned char *mem; // frame, cursor, page memory buffer + int found; // last delete or insert was found int err; // last error } BtDb; @@ -247,9 +275,10 @@ extern uid bt_uid (BtDb *bt, uint slot); extern uint bt_tod (BtDb *bt, uint slot); // BTree page number constants -#define ALLOC_page 0 -#define ROOT_page 1 -#define LEAF_page 2 +#define ALLOC_page 0 // allocation & lock manager hash table +#define ROOT_page 1 // root of the btree +#define LEAF_page 2 // first page of leaves +#define LATCH_page 3 // pages for lock manager // Number of levels to create in a new BTree @@ -302,7 +331,7 @@ extern uint bt_tod (BtDb *bt, uint slot); // Access macros to address slot and key values from the page -#define slotptr(page, slot) (((BtSlot *)(page+1)) + (slot-1)) +#define slotptr(page, slot) (page->table + slot-1) #define keyptr(page, slot) ((BtKey)((unsigned char*)(page) + slotptr(page, slot)->off)) void bt_putid(unsigned char *dest, uid id) @@ -324,6 +353,310 @@ int i; return id; } +// Latch Manager + +// wait until write lock mode is clear +// and add 1 to the share count + +void bt_spinreadlock(BtSpinLatch *latch) +{ +ushort prev; + + do { + // obtain latch mutex +#ifdef unix + if( __sync_fetch_and_or((ushort *)latch, Mutex) & Mutex ) + continue; +#else + if( prev = _InterlockedOr16((ushort *)latch, Mutex) & Mutex ) + continue; +#endif + // see if exclusive request is granted or pending + + if( prev = !(latch->exclusive | latch->pending) ) +#ifdef unix + __sync_fetch_and_add((ushort *)latch, Share); +#else + _InterlockedExchangeAdd16 ((ushort *)latch, Share); +#endif + +#ifdef unix + __sync_fetch_and_and ((ushort *)latch, ~Mutex); +#else + _InterlockedAnd16((ushort *)latch, ~Mutex); +#endif + + if( prev ) + return; +#ifdef unix + } while( sched_yield(), 1 ); +#else + } while( SwitchToThread(), 1 ); +#endif +} + +// wait for other read and write latches to relinquish + +void bt_spinwritelock(BtSpinLatch *latch) +{ + do { +#ifdef unix + if( __sync_fetch_and_or((ushort *)latch, Mutex | Pending) & Mutex ) + continue; +#else + if( _InterlockedOr16((ushort *)latch, Mutex | Pending) & Mutex ) + continue; +#endif + if( !(latch->share | latch->exclusive) ) { +#ifdef unix + __sync_fetch_and_or((ushort *)latch, Write); + __sync_fetch_and_and ((ushort *)latch, ~(Mutex | Pending)); +#else + _InterlockedOr16((ushort *)latch, Write); + _InterlockedAnd16((ushort *)latch, ~(Mutex | Pending)); +#endif + return; + } + +#ifdef unix + __sync_fetch_and_and ((ushort *)latch, ~Mutex); +#else + _InterlockedAnd16((ushort *)latch, ~Mutex); +#endif + +#ifdef unix + } while( sched_yield(), 1 ); +#else + } while( SwitchToThread(), 1 ); +#endif +} + +// try to obtain write lock + +// return 1 if obtained, +// 0 otherwise + +int bt_spinwritetry(BtSpinLatch *latch) +{ +ushort prev; + +#ifdef unix + if( prev = __sync_fetch_and_or((ushort *)latch, Mutex), prev & Mutex ) + return 0; +#else + if( prev = _InterlockedOr16((ushort *)latch, Mutex), prev & Mutex ) + return 0; +#endif + // take write access if all bits are clear + + if( !prev ) +#ifdef unix + __sync_fetch_and_or ((ushort *)latch, Write); +#else + _InterlockedOr16((ushort *)latch, Write); +#endif + +#ifdef unix + __sync_fetch_and_and ((ushort *)latch, ~Mutex); +#else + _InterlockedAnd16((ushort *)latch, ~Mutex); +#endif + return !prev; +} + +// clear write mode + +void bt_spinreleasewrite(BtSpinLatch *latch) +{ +#ifdef unix + __sync_fetch_and_and ((ushort *)latch, ~Write); +#else + _InterlockedAnd16((ushort *)latch, ~Write); +#endif +} + +// decrement reader count + +void bt_spinreleaseread(BtSpinLatch *latch) +{ +#ifdef unix + __sync_fetch_and_add((ushort *)latch, -Share); +#else + _InterlockedExchangeAdd16 ((ushort *)latch, -Share); +#endif +} + +// link latch table entry into latch hash table + +void bt_latchlink (BtDb *bt, ushort hashidx, ushort victim, uid page_no) +{ +BtLatchSet *set = bt->mgr->latchsets + victim; + + if( set->next = bt->mgr->latchmgr->table[hashidx].slot ) + bt->mgr->latchsets[set->next].prev = victim; + + bt->mgr->latchmgr->table[hashidx].slot = victim; + set->page_no = page_no; + set->hash = hashidx; + set->prev = 0; +} + +// release latch pin + +void bt_unpinlatch (BtLatchSet *set) +{ +#ifdef unix + __sync_fetch_and_add(&set->pin, -1); +#else + _InterlockedDecrement16 (&set->pin); +#endif +} + +// find existing latchset or inspire new one +// return with latchset pinned + +BtLatchSet *bt_pinlatch (BtDb *bt, uid page_no) +{ +ushort hashidx = page_no % bt->mgr->latchmgr->latchhash; +ushort slot, avail = 0, victim, idx; +BtLatchSet *set; + + // obtain read lock on hash table entry + + bt_spinreadlock(bt->mgr->latchmgr->table[hashidx].latch); + + if( slot = bt->mgr->latchmgr->table[hashidx].slot ) do + { + set = bt->mgr->latchsets + slot; + if( page_no == set->page_no ) + break; + } while( slot = set->next ); + + if( slot ) { +#ifdef unix + __sync_fetch_and_add(&set->pin, 1); +#else + _InterlockedIncrement16 (&set->pin); +#endif + } + + bt_spinreleaseread (bt->mgr->latchmgr->table[hashidx].latch); + + if( slot ) + return set; + + // try again, this time with write lock + + bt_spinwritelock(bt->mgr->latchmgr->table[hashidx].latch); + + if( slot = bt->mgr->latchmgr->table[hashidx].slot ) do + { + set = bt->mgr->latchsets + slot; + if( page_no == set->page_no ) + break; + if( !set->pin && !avail ) + avail = slot; + } while( slot = set->next ); + + // found our entry, or take over an unpinned one + + if( slot || (slot = avail) ) { + set = bt->mgr->latchsets + slot; +#ifdef unix + __sync_fetch_and_add(&set->pin, 1); +#else + _InterlockedIncrement16 (&set->pin); +#endif + set->page_no = page_no; + bt_spinreleasewrite(bt->mgr->latchmgr->table[hashidx].latch); + return set; + } + + // see if there are any unused entries +#ifdef unix + victim = __sync_fetch_and_add (&bt->mgr->latchmgr->latchdeployed, 1) + 1; +#else + victim = _InterlockedIncrement16 (&bt->mgr->latchmgr->latchdeployed); +#endif + + if( victim < bt->mgr->latchmgr->latchtotal ) { + set = bt->mgr->latchsets + victim; +#ifdef unix + __sync_fetch_and_add(&set->pin, 1); +#else + _InterlockedIncrement16 (&set->pin); +#endif + bt_latchlink (bt, hashidx, victim, page_no); + bt_spinreleasewrite (bt->mgr->latchmgr->table[hashidx].latch); + return set; + } + +#ifdef unix + victim = __sync_fetch_and_add (&bt->mgr->latchmgr->latchdeployed, -1); +#else + victim = _InterlockedDecrement16 (&bt->mgr->latchmgr->latchdeployed); +#endif + // find and reuse previous lock entry + + while( 1 ) { +#ifdef unix + victim = __sync_fetch_and_add(&bt->mgr->latchmgr->latchvictim, 1); +#else + victim = _InterlockedIncrement16 (&bt->mgr->latchmgr->latchvictim) - 1; +#endif + // we don't use slot zero + + if( victim %= bt->mgr->latchmgr->latchtotal ) + set = bt->mgr->latchsets + victim; + else + continue; + + // take control of our slot + // from other threads + + if( set->pin || !bt_spinwritetry (set->busy) ) + continue; + + idx = set->hash; + + // try to get write lock on hash chain + // skip entry if not obtained + // or has outstanding locks + + if( !bt_spinwritetry (bt->mgr->latchmgr->table[idx].latch) ) { + bt_spinreleasewrite (set->busy); + continue; + } + + if( set->pin ) { + bt_spinreleasewrite (set->busy); + bt_spinreleasewrite (bt->mgr->latchmgr->table[idx].latch); + continue; + } + + // unlink our available victim from its hash chain + + if( set->prev ) + bt->mgr->latchsets[set->prev].next = set->next; + else + bt->mgr->latchmgr->table[idx].slot = set->next; + + if( set->next ) + bt->mgr->latchsets[set->next].prev = set->prev; + + bt_spinreleasewrite (bt->mgr->latchmgr->table[idx].latch); +#ifdef unix + __sync_fetch_and_add(&set->pin, 1); +#else + _InterlockedIncrement16 (&set->pin); +#endif + bt_latchlink (bt, hashidx, victim, page_no); + bt_spinreleasewrite (bt->mgr->latchmgr->table[hashidx].latch); + bt_spinreleasewrite (set->busy); + return set; + } +} + void bt_mgrclose (BtMgr *mgr) { BtPool *pool; @@ -346,6 +679,14 @@ uint slot; #endif } +#ifdef unix + munmap (mgr->latchsets, mgr->latchmgr->nlatchpage * mgr->page_size); + munmap (mgr->latchmgr, mgr->page_size); +#else + FlushViewOfFile(mgr->latchmgr, 0); + UnmapViewOfFile(mgr->latchmgr); + CloseHandle(mgr->halloc); +#endif #ifdef unix close (mgr->idx); free (mgr->pool); @@ -384,13 +725,14 @@ void bt_close (BtDb *bt) BtMgr *bt_mgr (char *name, uint mode, uint bits, uint poolmax, uint segsize, uint hashsize) { -uint lvl, attr, cacheblk, last; -BtPage alloc; -int lockmode; +uint lvl, attr, cacheblk, last, slot, idx; +uint nlatchpage, latchhash; +BtLatchMgr *latchmgr; off64_t size; uint amt[1]; BtMgr* mgr; BtKey key; +int flag; #ifndef unix SYSTEM_INFO sysinfo[1]; @@ -409,19 +751,8 @@ SYSTEM_INFO sysinfo[1]; #ifdef unix mgr = calloc (1, sizeof(BtMgr)); - switch (mode & 0x7fff) - { - case BT_rw: - mgr->idx = open ((char*)name, O_RDWR | O_CREAT, 0666); - lockmode = 1; - break; + mgr->idx = open ((char*)name, O_RDWR | O_CREAT, 0666); - case BT_ro: - default: - mgr->idx = open ((char*)name, O_RDONLY); - lockmode = 0; - break; - } if( mgr->idx == -1 ) return free(mgr), NULL; @@ -430,19 +761,8 @@ SYSTEM_INFO sysinfo[1]; #else mgr = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, sizeof(BtMgr)); attr = FILE_ATTRIBUTE_NORMAL; - switch (mode & 0x7fff) - { - case BT_rw: - mgr->idx = CreateFile(name, GENERIC_READ| GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, attr, NULL); - lockmode = 1; - break; + mgr->idx = CreateFile(name, GENERIC_READ| GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, attr, NULL); - case BT_ro: - default: - mgr->idx = CreateFile(name, GENERIC_READ, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, attr, NULL); - lockmode = 0; - break; - } if( mgr->idx == INVALID_HANDLE_VALUE ) return GlobalFree(mgr), NULL; @@ -452,26 +772,26 @@ SYSTEM_INFO sysinfo[1]; #endif #ifdef unix - alloc = malloc (BT_maxpage); + latchmgr = malloc (BT_maxpage); *amt = 0; // read minimum page size to get root info if( size = lseek (mgr->idx, 0L, 2) ) { - if( pread(mgr->idx, alloc, BT_minpage, 0) == BT_minpage ) - bits = alloc->bits; + if( pread(mgr->idx, latchmgr, BT_minpage, 0) == BT_minpage ) + bits = latchmgr->alloc->bits; else - return free(mgr), free(alloc), NULL; + return free(mgr), free(latchmgr), NULL; } else if( mode == BT_ro ) - return bt_mgrclose (mgr), NULL; + return free(latchmgr), bt_mgrclose (mgr), NULL; #else - alloc = VirtualAlloc(NULL, BT_maxpage, MEM_COMMIT, PAGE_READWRITE); + latchmgr = VirtualAlloc(NULL, BT_maxpage, MEM_COMMIT, PAGE_READWRITE); size = GetFileSize(mgr->idx, amt); if( size || *amt ) { - if( !ReadFile(mgr->idx, (char *)alloc, BT_minpage, amt, NULL) ) + if( !ReadFile(mgr->idx, (char *)latchmgr, BT_minpage, amt, NULL) ) return bt_mgrclose (mgr), NULL; - bits = alloc->bits; + bits = latchmgr->alloc->bits; } else if( mode == BT_ro ) return bt_mgrclose (mgr), NULL; #endif @@ -504,53 +824,69 @@ SYSTEM_INFO sysinfo[1]; #ifdef unix mgr->pool = calloc (poolmax, sizeof(BtPool)); mgr->hash = calloc (hashsize, sizeof(ushort)); - mgr->latch = calloc (hashsize, sizeof(BtLatch)); + mgr->latch = calloc (hashsize, sizeof(BtSpinLatch)); mgr->pooladvise = calloc (poolmax, (mgr->poolmask + 8) / 8); #else mgr->pool = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, poolmax * sizeof(BtPool)); mgr->hash = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, hashsize * sizeof(ushort)); - mgr->latch = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, hashsize * sizeof(BtLatch)); + mgr->latch = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, hashsize * sizeof(BtSpinLatch)); #endif if( size || *amt ) - goto mgrxit; + goto mgrlatch; + + // initialize an empty b-tree with latch page, root page, page of leaves + // and page(s) of latches + + memset (latchmgr, 0, 1 << bits); + nlatchpage = BT_latchtable / (mgr->page_size / sizeof(BtLatchSet)) + 1; + bt_putid(latchmgr->alloc->right, MIN_lvl+1+nlatchpage); + latchmgr->alloc->bits = mgr->page_bits; + + latchmgr->nlatchpage = nlatchpage; + latchmgr->latchtotal = nlatchpage * (mgr->page_size / sizeof(BtLatchSet)); + + // initialize latch manager - // initializes an empty b-tree with root page and page of leaves + latchhash = (mgr->page_size - sizeof(BtLatchMgr)) / sizeof(BtHashEntry); - memset (alloc, 0, 1 << bits); - bt_putid(alloc->right, MIN_lvl+1); - alloc->bits = mgr->page_bits; + // size of hash table = total number of latchsets + + if( latchhash > latchmgr->latchtotal ) + latchhash = latchmgr->latchtotal; + + latchmgr->latchhash = latchhash; #ifdef unix - if( write (mgr->idx, alloc, mgr->page_size) < mgr->page_size ) + if( write (mgr->idx, latchmgr, mgr->page_size) < mgr->page_size ) return bt_mgrclose (mgr), NULL; #else - if( !WriteFile (mgr->idx, (char *)alloc, mgr->page_size, amt, NULL) ) + if( !WriteFile (mgr->idx, (char *)latchmgr, mgr->page_size, amt, NULL) ) return bt_mgrclose (mgr), NULL; if( *amt < mgr->page_size ) return bt_mgrclose (mgr), NULL; #endif - memset (alloc, 0, 1 << bits); - alloc->bits = mgr->page_bits; + memset (latchmgr, 0, 1 << bits); + latchmgr->alloc->bits = mgr->page_bits; for( lvl=MIN_lvl; lvl--; ) { - slotptr(alloc, 1)->off = mgr->page_size - 3; - bt_putid(slotptr(alloc, 1)->id, lvl ? MIN_lvl - lvl + 1 : 0); // next(lower) page number - key = keyptr(alloc, 1); + slotptr(latchmgr->alloc, 1)->off = mgr->page_size - 3; + bt_putid(slotptr(latchmgr->alloc, 1)->id, lvl ? MIN_lvl - lvl + 1 : 0); // next(lower) page number + key = keyptr(latchmgr->alloc, 1); key->len = 2; // create stopper key key->key[0] = 0xff; key->key[1] = 0xff; - alloc->min = mgr->page_size - 3; - alloc->lvl = lvl; - alloc->cnt = 1; - alloc->act = 1; + latchmgr->alloc->min = mgr->page_size - 3; + latchmgr->alloc->lvl = lvl; + latchmgr->alloc->cnt = 1; + latchmgr->alloc->act = 1; #ifdef unix - if( write (mgr->idx, alloc, mgr->page_size) < mgr->page_size ) + if( write (mgr->idx, latchmgr, mgr->page_size) < mgr->page_size ) return bt_mgrclose (mgr), NULL; #else - if( !WriteFile (mgr->idx, (char *)alloc, mgr->page_size, amt, NULL) ) + if( !WriteFile (mgr->idx, (char *)latchmgr, mgr->page_size, amt, NULL) ) return bt_mgrclose (mgr), NULL; if( *amt < mgr->page_size ) @@ -558,32 +894,52 @@ SYSTEM_INFO sysinfo[1]; #endif } - // create empty page area by writing last page of first - // segment area (other pages are zeroed by O/S) + // clear out latch manager locks + // and rest of pages to round out segment - if( mgr->poolmask ) { - memset(alloc, 0, mgr->page_size); - last = mgr->poolmask; - - while( last < MIN_lvl + 1 ) - last += mgr->poolmask + 1; + memset(latchmgr, 0, mgr->page_size); + last = MIN_lvl + 1; + while( last <= ((MIN_lvl + 1 + nlatchpage) | mgr->poolmask) ) { #ifdef unix - pwrite(mgr->idx, alloc, mgr->page_size, last << mgr->page_bits); + pwrite(mgr->idx, latchmgr, mgr->page_size, last << mgr->page_bits); #else SetFilePointer (mgr->idx, last << mgr->page_bits, NULL, FILE_BEGIN); - if( !WriteFile (mgr->idx, (char *)alloc, mgr->page_size, amt, NULL) ) + if( !WriteFile (mgr->idx, (char *)latchmgr, mgr->page_size, amt, NULL) ) return bt_mgrclose (mgr), NULL; if( *amt < mgr->page_size ) return bt_mgrclose (mgr), NULL; #endif + last++; } -mgrxit: +mgrlatch: +#ifdef unix + flag = PROT_READ | PROT_WRITE; + mgr->latchmgr = mmap (0, mgr->page_size, flag, MAP_SHARED, mgr->idx, ALLOC_page * mgr->page_size); + if( mgr->latchmgr == MAP_FAILED ) + return bt_mgrclose (mgr), NULL; + mgr->latchsets = (BtLatchSet *)mmap (0, mgr->latchmgr->nlatchpage * mgr->page_size, flag, MAP_SHARED, mgr->idx, LATCH_page * mgr->page_size); + if( mgr->latchsets == MAP_FAILED ) + return bt_mgrclose (mgr), NULL; +#else + flag = PAGE_READWRITE; + mgr->halloc = CreateFileMapping(mgr->idx, NULL, flag, 0, (BT_latchtable / (mgr->page_size / sizeof(BtLatchSet)) + 1 + LATCH_page) * mgr->page_size, NULL); + if( !mgr->halloc ) + return bt_mgrclose (mgr), NULL; + + flag = FILE_MAP_WRITE; + mgr->latchmgr = MapViewOfFile(mgr->halloc, flag, 0, 0, (BT_latchtable / (mgr->page_size / sizeof(BtLatchSet)) + 1 + LATCH_page) * mgr->page_size); + if( !mgr->latchmgr ) + return GetLastError(), bt_mgrclose (mgr), NULL; + + mgr->latchsets = (void *)((char *)mgr->latchmgr + LATCH_page * mgr->page_size); +#endif + #ifdef unix - free (alloc); + free (latchmgr); #else - VirtualFree (alloc, 0, MEM_RELEASE); + VirtualFree (latchmgr, 0, MEM_RELEASE); #endif return mgr; } @@ -629,167 +985,6 @@ int ans; return 0; } -// Latch Manager - -int sys_futex(void *addr1, int op, int val1, struct timespec *timeout, void *addr2, int val3) -{ - return syscall(SYS_futex, addr1, op, val1, timeout, addr2, val3); -} - -// wait until write lock mode is clear -// and add 1 to the share count - -void bt_readlock(BtLatch *latch, int private) -{ -uint prev; - - if( private ) - private = FUTEX_PRIVATE_FLAG; - - while( 1 ) { - // obtain latch mutex - if( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex ) { - sched_yield(); - continue; - } - - // wait for writers to clear - // increment read waiters and wait - - if( latch->write || latch->writewait ) { - __sync_fetch_and_add ((uint *)latch, PendRd); - prev = __sync_fetch_and_and ((uint *)latch, ~Mutex) & ~Mutex; - sys_futex( (uint *)latch, FUTEX_WAIT_BITSET | private, prev, NULL, NULL, QueRd ); - __sync_fetch_and_sub ((uint *)latch, PendRd); - continue; - } - - // increment reader lock count - // and release latch mutex - - __sync_fetch_and_add ((uint *)latch, Share); - __sync_fetch_and_and ((uint *)latch, ~Mutex); - return; - } -} - -// wait for other read and write latches to relinquish - -void bt_writelock(BtLatch *latch, int private) -{ -uint prev; - - if( private ) - private = FUTEX_PRIVATE_FLAG; - - while( 1 ) { - // obtain latch mutex - if( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex ) { - sched_yield(); - continue; - } - - // wait for write and reader count to clear - - if( latch->write || latch->share ) { - __sync_fetch_and_add ((uint *)latch, PendWr); - prev = __sync_fetch_and_and ((uint *)latch, ~Mutex) & ~Mutex; - sys_futex( (uint *)latch, FUTEX_WAIT_BITSET | private, prev, NULL, NULL, QueWr ); - __sync_fetch_and_sub ((uint *)latch, PendWr); - continue; - } - - // take write mutex - // release latch mutex - - __sync_fetch_and_or ((uint *)latch, Write); - __sync_fetch_and_and ((uint *)latch, ~Mutex); - return; - } -} - -// try to obtain write lock - -// return 1 if obtained, -// 0 otherwise - -int bt_writetry(BtLatch *latch) -{ -int ans; - - // try for mutex, - // abandon request if not taken - - if( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex ) - return 0; - - // see if write mode is available - - if( !latch->write && !latch->share ) { - __sync_fetch_and_or ((uint *)latch, Write); - ans = 1; - } else - ans = 0; - - // release latch mutex - - __sync_fetch_and_and ((uint *)latch, ~Mutex); - return ans; -} - -// clear write lock - -void bt_releasewrite(BtLatch *latch, int private) -{ - if( private ) - private = FUTEX_PRIVATE_FLAG; - - // obtain latch mutex - - while( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex ) - sched_yield(); - - __sync_fetch_and_and ((uint *)latch, ~Write); - - // favor writers - - if( latch->writewait ) - if( sys_futex( (uint *)latch, FUTEX_WAKE_BITSET | private, 1, NULL, NULL, QueWr ) ) - goto wakexit; - - if( latch->readwait ) - sys_futex( (uint *)latch, FUTEX_WAKE_BITSET | private, INT_MAX, NULL, NULL, QueRd ); - - // release latch mutex - -wakexit: - __sync_fetch_and_and ((uint *)latch, ~Mutex); -} - -// decrement reader count - -void bt_releaseread(BtLatch *latch, int private) -{ - if( private ) - private = FUTEX_PRIVATE_FLAG; - - // obtain latch mutex - - while( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex ) - sched_yield(); - - __sync_fetch_and_sub ((uint *)latch, Share); - - // wake waiting writers - - if( !latch->share && latch->writewait ) - sys_futex( (uint *)latch, FUTEX_WAKE_BITSET | private, 1, NULL, NULL, QueWr ); - - // release latch mutex - - __sync_fetch_and_and ((uint *)latch, ~Mutex); -} - // Buffer Pool mgr // find segment in pool @@ -896,10 +1091,43 @@ int flag; return bt->err = 0; } +// calculate page within pool + +BtPage bt_page (BtDb *bt, BtPool *pool, uid page_no) +{ +uint subpage = (uint)(page_no & bt->mgr->poolmask); // page within mapping +BtPage page; + + page = (BtPage)(pool->map + (subpage << bt->mgr->page_bits)); +#ifdef unix + { + uint idx = subpage / 8; + uint bit = subpage % 8; + + if( ~((bt->mgr->pooladvise + pool->slot * ((bt->mgr->poolmask + 8)/8))[idx] >> bit) & 1 ) { + madvise (page, bt->mgr->page_size, MADV_WILLNEED); + (bt->mgr->pooladvise + pool->slot * ((bt->mgr->poolmask + 8)/8))[idx] |= 1 << bit; + } + } +#endif + return page; +} + +// release pool pin + +void bt_unpinpool (BtPool *pool) +{ +#ifdef unix + __sync_fetch_and_add(&pool->pin, -1); +#else + _InterlockedDecrement16 (&pool->pin); +#endif +} + // find or place requested page in segment-pool // return pool table entry, incrementing pin -BtPool *bt_pinpage(BtDb *bt, uid page_no) +BtPool *bt_pinpool(BtDb *bt, uid page_no) { BtPool *pool, *node, *next; uint slot, idx, victim; @@ -907,7 +1135,7 @@ uint slot, idx, victim; // lock hash table chain idx = (uint)(page_no >> bt->mgr->seg_bits) % bt->mgr->hashsize; - bt_readlock (&bt->mgr->latch[idx], 1); + bt_spinreadlock (&bt->mgr->latch[idx]); // look up in hash table @@ -915,17 +1143,17 @@ uint slot, idx, victim; #ifdef unix __sync_fetch_and_add(&pool->pin, 1); #else - _InterlockedIncrement (&pool->pin); + _InterlockedIncrement16 (&pool->pin); #endif - bt_releaseread (&bt->mgr->latch[idx], 1); + bt_spinreleaseread (&bt->mgr->latch[idx]); pool->lru++; return pool; } // upgrade to write lock - bt_releaseread (&bt->mgr->latch[idx], 1); - bt_writelock (&bt->mgr->latch[idx], 1); + bt_spinreleaseread (&bt->mgr->latch[idx]); + bt_spinwritelock (&bt->mgr->latch[idx]); // try to find page in pool with write lock @@ -933,9 +1161,9 @@ uint slot, idx, victim; #ifdef unix __sync_fetch_and_add(&pool->pin, 1); #else - _InterlockedIncrement (&pool->pin); + _InterlockedIncrement16 (&pool->pin); #endif - bt_releasewrite (&bt->mgr->latch[idx], 1); + bt_spinreleasewrite (&bt->mgr->latch[idx]); pool->lru++; return pool; } @@ -946,7 +1174,7 @@ uint slot, idx, victim; #ifdef unix slot = __sync_fetch_and_add(&bt->mgr->poolcnt, 1); #else - slot = _InterlockedIncrement (&bt->mgr->poolcnt) - 1; + slot = _InterlockedIncrement16 (&bt->mgr->poolcnt) - 1; #endif if( ++slot < bt->mgr->poolmax ) { @@ -960,9 +1188,9 @@ uint slot, idx, victim; #ifdef unix __sync_fetch_and_add(&pool->pin, 1); #else - _InterlockedIncrement (&pool->pin); + _InterlockedIncrement16 (&pool->pin); #endif - bt_releasewrite (&bt->mgr->latch[idx], 1); + bt_spinreleasewrite (&bt->mgr->latch[idx]); return pool; } @@ -972,7 +1200,7 @@ uint slot, idx, victim; #ifdef unix __sync_fetch_and_add(&bt->mgr->poolcnt, -1); #else - _InterlockedDecrement (&bt->mgr->poolcnt); + _InterlockedDecrement16 (&bt->mgr->poolcnt); #endif while( 1 ) { @@ -986,7 +1214,7 @@ uint slot, idx, victim; // try to get write lock // skip entry if not obtained - if( !bt_writetry (&bt->mgr->latch[victim]) ) + if( !bt_spinwritetry (&bt->mgr->latch[victim]) ) continue; // if pool entry is empty @@ -994,7 +1222,7 @@ uint slot, idx, victim; // skip this entry if( !(pool = bt_findlru(bt, bt->mgr->hash[victim])) ) { - bt_releasewrite (&bt->mgr->latch[victim], 1); + bt_spinreleasewrite (&bt->mgr->latch[victim]); continue; } @@ -1010,7 +1238,7 @@ uint slot, idx, victim; if( node = pool->hashnext ) node->hashprev = pool->hashprev; - bt_releasewrite (&bt->mgr->latch[victim], 1); + bt_spinreleasewrite (&bt->mgr->latch[victim]); // remove old file mapping #ifdef unix @@ -1032,217 +1260,117 @@ uint slot, idx, victim; #ifdef unix __sync_fetch_and_add(&pool->pin, 1); #else - _InterlockedIncrement (&pool->pin); + _InterlockedIncrement16 (&pool->pin); #endif - bt_releasewrite (&bt->mgr->latch[idx], 1); + bt_spinreleasewrite (&bt->mgr->latch[idx]); return pool; } } // place write, read, or parent lock on requested page_no. -// pin to buffer pool and return page pointer -BTERR bt_lockpage(BtDb *bt, uid page_no, BtLock mode, BtPage *pageptr) +void bt_lockpage(BtLock mode, BtLatchSet *set) { -uint subpage; -BtPool *pool; -BtPage page; - - // find/create maping in pool table - // and pin our pool slot - - if( pool = bt_pinpage(bt, page_no) ) - subpage = (uint)(page_no & bt->mgr->poolmask); // page within mapping - else - return bt->err; - - page = (BtPage)(pool->map + (subpage << bt->mgr->page_bits)); -#ifdef unix - { - uint idx = subpage / 8; - uint bit = subpage % 8; - - if( ~((bt->mgr->pooladvise + pool->slot * ((bt->mgr->poolmask + 8)/8))[idx] >> bit) & 1 ) { - madvise (page, bt->mgr->page_size, MADV_WILLNEED); - (bt->mgr->pooladvise + pool->slot * ((bt->mgr->poolmask + 8)/8))[idx] |= 1 << bit; - } - } -#endif - switch( mode ) { case BtLockRead: - bt_readlock (page->latch->readwr, 0); + bt_spinreadlock (set->readwr); break; case BtLockWrite: - bt_writelock (page->latch->readwr, 0); + bt_spinwritelock (set->readwr); break; case BtLockAccess: - bt_readlock (page->latch->access, 0); + bt_spinreadlock (set->access); break; case BtLockDelete: - bt_writelock (page->latch->access, 0); + bt_spinwritelock (set->access); break; case BtLockParent: - bt_writelock (page->latch->parent, 0); + bt_spinwritelock (set->parent); break; - default: - return bt->err = BTERR_lock; } - - if( pageptr ) - *pageptr = page; - return bt->err = 0; } // remove write, read, or parent lock on requested page -BTERR bt_unlockpage(BtDb *bt, uid page_no, BtLock mode) +void bt_unlockpage(BtLock mode, BtLatchSet *set) { -uint subpage, idx; -BtPool *pool; -BtPage page; - - // since page is pinned - // it should still be in the buffer pool - // and is in no danger of being a victim for reuse - - idx = (uint)(page_no >> bt->mgr->seg_bits) % bt->mgr->hashsize; - bt_readlock (&bt->mgr->latch[idx], 1); - - if( pool = bt_findpool(bt, page_no, idx) ) - subpage = (uint)(page_no & bt->mgr->poolmask); - else - return bt->err = BTERR_hash; - - bt_releaseread (&bt->mgr->latch[idx], 1); - page = (BtPage)(pool->map + (subpage << bt->mgr->page_bits)); - switch( mode ) { case BtLockRead: - bt_releaseread (page->latch->readwr, 0); + bt_spinreleaseread (set->readwr); break; case BtLockWrite: - bt_releasewrite (page->latch->readwr, 0); + bt_spinreleasewrite (set->readwr); break; case BtLockAccess: - bt_releaseread (page->latch->access, 0); + bt_spinreleaseread (set->access); break; case BtLockDelete: - bt_releasewrite (page->latch->access, 0); + bt_spinreleasewrite (set->access); break; case BtLockParent: - bt_releasewrite (page->latch->parent, 0); + bt_spinreleasewrite (set->parent); break; - default: - return bt->err = BTERR_lock; } - -#ifdef unix - __sync_fetch_and_add(&pool->pin, -1); -#else - _InterlockedDecrement (&pool->pin); -#endif - return bt->err = 0; -} - -// deallocate a deleted page -// place on free chain out of allocator page - -BTERR bt_freepage(BtDb *bt, uid page_no) -{ - // obtain delete lock on deleted page - - if( bt_lockpage(bt, page_no, BtLockDelete, NULL) ) - return bt->err; - - // obtain write lock on deleted page - - if( bt_lockpage(bt, page_no, BtLockWrite, &bt->temp) ) - return bt->err; - - // lock allocation page - - if ( bt_lockpage(bt, ALLOC_page, BtLockWrite, &bt->alloc) ) - return bt->err; - - // store chain in second right - bt_putid(bt->temp->right, bt_getid(bt->alloc[1].right)); - bt_putid(bt->alloc[1].right, page_no); - - // unlock page zero - - if( bt_unlockpage(bt, ALLOC_page, BtLockWrite) ) - return bt->err; - - // remove write lock on deleted node - - if( bt_unlockpage(bt, page_no, BtLockWrite) ) - return bt->err; - - // remove delete lock on deleted node - - if( bt_unlockpage(bt, page_no, BtLockDelete) ) - return bt->err; - - return 0; } // allocate a new page and write page into it uid bt_newpage(BtDb *bt, BtPage page) { +BtLatchSet *set; +BtPool *pool; uid new_page; BtPage pmap; -int subpage; int reuse; - // lock page zero + // lock allocation page - if( bt_lockpage(bt, ALLOC_page, BtLockWrite, &bt->alloc) ) - return 0; + bt_spinwritelock(bt->mgr->latchmgr->lock); // use empty chain first // else allocate empty page - if( new_page = bt_getid(bt->alloc[1].right) ) { - if( bt_lockpage (bt, new_page, BtLockWrite, &bt->temp) ) - return 0; - bt_putid(bt->alloc[1].right, bt_getid(bt->temp->right)); - if( bt_unlockpage (bt, new_page, BtLockWrite) ) + if( new_page = bt_getid(bt->mgr->latchmgr->alloc[1].right) ) { + if( pool = bt_pinpool (bt, new_page) ) + pmap = bt_page (bt, pool, new_page); + else return 0; + bt_putid(bt->mgr->latchmgr->alloc[1].right, bt_getid(pmap->right)); + bt_unpinpool (pool); reuse = 1; } else { - new_page = bt_getid(bt->alloc->right); - bt_putid(bt->alloc->right, new_page+1); + new_page = bt_getid(bt->mgr->latchmgr->alloc->right); + bt_putid(bt->mgr->latchmgr->alloc->right, new_page+1); reuse = 0; } - #ifdef unix - // if writing first page of pool block - // expand file thru last page in the block - - if( !reuse && (new_page & bt->mgr->poolmask) == 0 ) - if( pwrite(bt->mgr->idx, bt->zero, bt->mgr->page_size, (new_page | bt->mgr->poolmask) << bt->mgr->page_bits) < bt->mgr->page_size ) + if ( pwrite(bt->mgr->idx, page, bt->mgr->page_size, new_page << bt->mgr->page_bits) < bt->mgr->page_size ) return bt->err = BTERR_wrt, 0; -#endif - // unlock page allocation page - if( bt_unlockpage(bt, ALLOC_page, BtLockWrite) ) - return 0; + // if writing first page of pool block, zero last page in the block + if ( !reuse && bt->mgr->poolmask > 0 && (new_page & bt->mgr->poolmask) == 0 ) + { + // use zero buffer to write zeros + memset(bt->zero, 0, bt->mgr->page_size); + if ( pwrite(bt->mgr->idx,bt->zero, bt->mgr->page_size, (new_page | bt->mgr->poolmask) << bt->mgr->page_bits) < bt->mgr->page_size ) + return bt->err = BTERR_wrt, 0; + } +#else // bring new page into pool and copy page. - // on Windows, this will extend the file into the new page. + // this will extend the file into the new pages. - if( bt_lockpage(bt, new_page, BtLockWrite, &pmap) ) + if( pool = bt_pinpool (bt, new_page) ) + pmap = bt_page (bt, pool, new_page); + else return 0; - // copy source page but leave latch area intact - - memcpy((char *)pmap + sizeof(BtLatchSet), (char *)page + sizeof(BtLatchSet), bt->mgr->page_size - sizeof(BtLatchSet)); - - if( bt_unlockpage (bt, new_page, BtLockWrite) ) - return 0; + memcpy(pmap, page, bt->mgr->page_size); + bt_unpinpool (pool); +#endif + // unlock allocation latch and return new page no + bt_spinreleasewrite(bt->mgr->latchmgr->lock); return new_page; } @@ -1282,36 +1410,49 @@ uint good = 0; int bt_loadpage (BtDb *bt, unsigned char *key, uint len, uint lvl, uint lock) { uid page_no = ROOT_page, prevpage = 0; +BtLatchSet *set, *prevset; uint drill = 0xff, slot; uint mode, prevmode; +BtPool *prevpool; // start at root of btree and drill down + bt->set = NULL; + do { // determine lock mode of drill level mode = (lock == BtLockWrite) && (drill == lvl) ? BtLockWrite : BtLockRead; + bt->set = bt_pinlatch (bt, page_no); bt->page_no = page_no; + // pin page contents + + if( bt->pool = bt_pinpool (bt, page_no) ) + bt->page = bt_page (bt, bt->pool, page_no); + else + return 0; + // obtain access lock using lock chaining with Access mode if( page_no > ROOT_page ) - if( bt_lockpage(bt, page_no, BtLockAccess, NULL) ) - return 0; + bt_lockpage(BtLockAccess, bt->set); - if( prevpage ) - if( bt_unlockpage(bt, prevpage, prevmode) ) - return 0; + // release & unpin parent page + + if( prevpage ) { + bt_unlockpage(prevmode, prevset); + bt_unpinlatch (prevset); + bt_unpinpool (prevpool); + prevpage = 0; + } // obtain read lock using lock chaining - // and pin page contents - if( bt_lockpage(bt, page_no, mode, &bt->page) ) - return 0; + bt_lockpage(mode, bt->set); if( page_no > ROOT_page ) - if( bt_unlockpage(bt, page_no, BtLockAccess) ) - return 0; + bt_unlockpage(BtLockAccess, bt->set); // re-read and re-lock root after determining actual level of root @@ -1321,11 +1462,12 @@ uint mode, prevmode; drill = bt->page->lvl; - if( lock == BtLockWrite && drill == lvl ) - if( bt_unlockpage(bt, page_no, mode) ) - return 0; - else - continue; + if( lock == BtLockWrite && drill == lvl ) { + bt_unlockpage(mode, bt->set); + bt_unpinlatch (bt->set); + bt_unpinpool (bt->pool); + continue; + } } // find key on page at this level @@ -1358,6 +1500,8 @@ uint mode, prevmode; slideright: prevpage = bt->page_no; + prevpool = bt->pool; + prevset = bt->set; prevmode = mode; } while( page_no ); @@ -1373,8 +1517,11 @@ slideright: BTERR bt_deletekey (BtDb *bt, unsigned char *key, uint len, uint lvl) { unsigned char lowerkey[256], higherkey[256]; +BtLatchSet *rset, *set; +BtPool *pool, *rpool; uid page_no, right; uint slot, tod; +BtPage rpage; BtKey ptr; if( slot = bt_loadpage (bt, key, len, lvl, BtLockWrite) ) @@ -1384,8 +1531,8 @@ BtKey ptr; // if key is found delete it, otherwise ignore request - if( !keycmp (ptr, key, len) ) - if( slotptr(bt->page, slot)->dead == 0 ) { + if( bt->found = !keycmp (ptr, key, len) ) + if( bt->found = slotptr(bt->page, slot)->dead == 0 ) { slotptr(bt->page,slot)->dead = 1; if( slot < bt->page->cnt ) bt->page->dirty = 1; @@ -1396,14 +1543,19 @@ BtKey ptr; right = bt_getid(bt->page->right); page_no = bt->page_no; + pool = bt->pool; + set = bt->set; - if( !right || bt->page->act ) - return bt_unlockpage(bt, page_no, BtLockWrite); + if( !right || bt->page->act ) { + bt_unlockpage(BtLockWrite, set); + bt_unpinlatch (set); + bt_unpinpool (pool); + return bt->err; + } // obtain Parent lock over write lock - if( bt_lockpage(bt, page_no, BtLockParent, NULL) ) - return bt->err; + bt_lockpage(BtLockParent, set); // keep copy of key to delete @@ -1412,27 +1564,32 @@ BtKey ptr; // lock and map right page - if ( bt_lockpage(bt, right, BtLockWrite, &bt->temp) ) + if( rpool = bt_pinpool (bt, right) ) + rpage = bt_page (bt, rpool, right); + else return bt->err; + rset = bt_pinlatch (bt, right); + bt_lockpage(BtLockWrite, rset); + // pull contents of next page into current empty page - memcpy((char *)bt->page + sizeof(BtLatchSet), (char *)bt->temp + sizeof(BtLatchSet), bt->mgr->page_size - sizeof(BtLatchSet)); + + memcpy (bt->page, rpage, bt->mgr->page_size); // keep copy of key to update - ptr = keyptr(bt->temp, bt->temp->cnt); + + ptr = keyptr(rpage, rpage->cnt); memcpy(higherkey, ptr, ptr->len + 1); // Mark right page as deleted and point it to left page // until we can post updates at higher level. - bt_putid(bt->temp->right, page_no); - bt->temp->kill = 1; - bt->temp->cnt = 0; + bt_putid(rpage->right, page_no); + rpage->kill = 1; + rpage->cnt = 0; - if( bt_unlockpage(bt, right, BtLockWrite) ) - return bt->err; - if( bt_unlockpage(bt, page_no, BtLockWrite) ) - return bt->err; + bt_unlockpage(BtLockWrite, rset); + bt_unlockpage(BtLockWrite, set); // delete old lower key to consolidated node @@ -1446,17 +1603,26 @@ BtKey ptr; if( bt_insertkey (bt, higherkey+1, *higherkey, lvl + 1, page_no, tod) ) return bt->err; - // obtain write lock and - // add right block to free chain + // add killed right block to free chain + // lock latch mgr - if( bt_freepage (bt, right) ) - return bt->err; + bt_spinwritelock(bt->mgr->latchmgr->lock); + + // store free chain in allocation page second right + bt_putid(rpage->right, bt_getid(bt->mgr->latchmgr->alloc[1].right)); + bt_putid(bt->mgr->latchmgr->alloc[1].right, right); + + // unlock latch mgr and unpin right page + + bt_spinreleasewrite(bt->mgr->latchmgr->lock); + bt_unpinlatch (rset); + bt_unpinpool (rpool); // remove ParentModify lock - if( bt_unlockpage(bt, page_no, BtLockParent) ) - return bt->err; - + bt_unlockpage(BtLockParent, set); + bt_unpinlatch (set); + bt_unpinpool (pool); return 0; } @@ -1481,27 +1647,28 @@ uid id; else id = 0; - if ( bt_unlockpage(bt, bt->page_no, BtLockRead) ) - return 0; - + bt_unlockpage (BtLockRead, bt->set); + bt_unpinlatch (bt->set); + bt_unpinpool (bt->pool); return id; } // check page for space available, // clean if necessary and return -// 0 - page needs splitting -// 1 - go ahead +// =0 - page needs splitting +// >0 - go ahead at returned slot -uint bt_cleanpage(BtDb *bt, uint amt) +uint bt_cleanpage(BtDb *bt, uint amt, uint slot) { uint nxt = bt->mgr->page_size; BtPage page = bt->page; uint cnt = 0, idx = 0; uint max = page->cnt; +uint newslot; BtKey key; - if( page->min >= (page->cnt+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 ) - return 1; + if( page->min >= (max+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 ) + return slot; // skip cleanup if nothing to reclaim @@ -1516,9 +1683,12 @@ BtKey key; page->dirty = 0; page->act = 0; + // always leave fence key in list + while( cnt++ < max ) { - // always leave fence key in list - if( cnt < max && slotptr(bt->frame,cnt)->dead ) + if( cnt == slot ) + newslot = idx + 1; + else if( cnt < max && slotptr(bt->frame,cnt)->dead ) continue; // copy key @@ -1536,8 +1706,8 @@ BtKey key; page->min = nxt; page->cnt = idx; - if( page->min >= (page->cnt+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 ) - return 1; + if( page->min >= (idx+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 ) + return newslot; return 0; } @@ -1583,9 +1753,12 @@ uid new_page; root->act = 2; root->lvl++; - // release root (bt->page) + // release and unpin root (bt->page) - return bt_unlockpage(bt, bt->page_no, BtLockWrite); + bt_unlockpage(BtLockWrite, bt->set); + bt_unpinlatch (bt->set); + bt_unpinpool (bt->pool); + return 0; } // split already locked full node @@ -1596,6 +1769,8 @@ BTERR bt_splitpage (BtDb *bt) uint cnt = 0, idx = 0, max, nxt = bt->mgr->page_size; unsigned char oldkey[256], lowerkey[256]; uid page_no = bt->page_no, right; +BtLatchSet *nset, *set = bt->set; +BtPool *pool = bt->pool; BtPage page = bt->page; uint lvl = page->lvl; uid new_page; @@ -1681,16 +1856,15 @@ uint tod; // obtain Parent/Write locks // for left and right node pages - if( bt_lockpage (bt, new_page, BtLockParent, NULL) ) - return bt->err; + nset = bt_pinlatch (bt, new_page); - if( bt_lockpage (bt, page_no, BtLockParent, NULL) ) - return bt->err; + bt_lockpage (BtLockParent, nset); + bt_lockpage (BtLockParent, set); // release wr lock on left page + // (keep the SMO in sequence) - if( bt_unlockpage (bt, page_no, BtLockWrite) ) - return bt->err; + bt_unlockpage (BtLockWrite, set); // insert new fence for reformulated left block @@ -1702,20 +1876,18 @@ uint tod; if( bt_insertkey (bt, oldkey+1, *oldkey, lvl + 1, new_page, tod) ) return bt->err; - // release Parent & Write locks - - if( bt_unlockpage (bt, new_page, BtLockParent) ) - return bt->err; - - if( bt_unlockpage (bt, page_no, BtLockParent) ) - return bt->err; + // release Parent locks + bt_unlockpage (BtLockParent, nset); + bt_unlockpage (BtLockParent, set); + bt_unpinlatch (nset); + bt_unpinlatch (set); + bt_unpinpool (pool); return 0; } // Insert new key into the btree at requested level. -// Level zero pages are leaf pages and are unlocked at exit. -// Interior pages remain locked. +// Level zero pages are leaf pages. Page is unlocked at exit. BTERR bt_insertkey (BtDb *bt, unsigned char *key, uint len, uint lvl, uid id, uint tod) { @@ -1737,16 +1909,19 @@ BtKey ptr; page = bt->page; - if( !keycmp (ptr, key, len) ) { + if( bt->found = !keycmp (ptr, key, len) ) { slotptr(page, slot)->dead = 0; slotptr(page, slot)->tod = tod; bt_putid(slotptr(page,slot)->id, id); - return bt_unlockpage(bt, bt->page_no, BtLockWrite); + bt_unlockpage(BtLockWrite, bt->set); + bt_unpinlatch(bt->set); + bt_unpinpool (bt->pool); + return bt->err; } // check if page has enough space - if( bt_cleanpage (bt, len) ) + if( slot = bt_cleanpage (bt, len, slot) ) break; if( bt_splitpage (bt) ) @@ -1779,7 +1954,10 @@ BtKey ptr; slotptr(page, slot)->tod = tod; slotptr(page, slot)->dead = 0; - return bt_unlockpage(bt, bt->page_no, BtLockWrite); + bt_unlockpage (BtLockWrite, bt->set); + bt_unpinlatch (bt->set); + bt_unpinpool (bt->pool); + return 0; } // cache page of keys into cursor and return starting slot for given key @@ -1792,9 +1970,9 @@ uint slot; if( slot = bt_loadpage (bt, key, len, 0, BtLockRead) ) memcpy (bt->cursor, bt->page, bt->mgr->page_size); bt->cursor_page = bt->page_no; - if ( bt_unlockpage(bt, bt->page_no, BtLockRead) ) - return 0; - + bt_unlockpage(BtLockRead, bt->set); + bt_unpinlatch (bt->set); + bt_unpinpool (bt->pool); return slot; } @@ -1803,7 +1981,9 @@ uint slot; uint bt_nextkey (BtDb *bt, uint slot) { -off64_t right; +BtPool *pool; +BtPage page; +uid right; do { right = bt_getid(bt->cursor->right); @@ -1820,14 +2000,19 @@ off64_t right; bt->cursor_page = right; - if( bt_lockpage(bt, right, BtLockRead, &bt->page) ) + if( pool = bt_pinpool (bt, right) ) + page = bt_page (bt, pool, right); + else return 0; - memcpy (bt->cursor, bt->page, bt->mgr->page_size); + bt->set = bt_pinlatch (bt, right); + bt_lockpage(BtLockRead, bt->set); - if ( bt_unlockpage(bt, right, BtLockRead) ) - return 0; + memcpy (bt->cursor, page, bt->mgr->page_size); + bt_unlockpage(BtLockRead, bt->set); + bt_unpinlatch (bt->set); + bt_unpinpool (pool); slot = 0; } while( 1 ); @@ -1849,9 +2034,56 @@ uint bt_tod(BtDb *bt, uint slot) return slotptr(bt->cursor,slot)->tod; } - #ifdef STANDALONE +void bt_latchaudit (BtDb *bt) +{ +ushort idx, hashidx; +BtLatchSet *set; +BtPool *pool; +BtPage page; +uid page_no; + +#ifdef unix + for( idx = 1; idx < bt->mgr->latchmgr->latchdeployed; idx++ ) { + set = bt->mgr->latchsets + idx; + if( *(ushort *)set->readwr || *(ushort *)set->access || *(ushort *)set->parent ) { + fprintf(stderr, "latchset %d locked for page %6x\n", idx, set->page_no); + *(ushort *)set->readwr = 0; + *(ushort *)set->access = 0; + *(ushort *)set->parent = 0; + } + if( set->pin ) { + fprintf(stderr, "latchset %d pinned\n", idx); + set->pin = 0; + } + } + + for( hashidx = 0; hashidx < bt->mgr->latchmgr->latchhash; hashidx++ ) { + if( *(uint *)bt->mgr->latchmgr->table[hashidx].latch ) + fprintf(stderr, "latchmgr locked\n"); + if( idx = bt->mgr->latchmgr->table[hashidx].slot ) do { + set = bt->mgr->latchsets + idx; + if( *(uint *)set->readwr || *(ushort *)set->access || *(ushort *)set->parent ) + fprintf(stderr, "latchset %d locked\n", idx); + if( set->hash != hashidx ) + fprintf(stderr, "latchset %d wrong hashidx\n", idx); + if( set->pin ) + fprintf(stderr, "latchset %d pinned\n", idx); + } while( idx = set->next ); + } + page_no = bt_getid(bt->mgr->latchmgr->alloc[1].right); + + while( page_no ) { + fprintf(stderr, "free: %.6x\n", (uint)page_no); + pool = bt_pinpool (bt, page_no); + page = bt_page (bt, pool, page_no); + page_no = bt_getid(page->right); + bt_unpinpool (pool); + } +#endif +} + typedef struct { char type, idx; char *infile; @@ -1874,6 +2106,7 @@ unsigned char key[256]; ThreadArg *args = arg; int ch, len = 0, slot; time_t tod[1]; +BtPool *pool; BtPage page; BtKey ptr; BtDb *bt; @@ -1884,6 +2117,12 @@ FILE *in; switch(args->type | 0x20) { + case 'a': + fprintf(stderr, "started latch mgr audit\n"); + bt_latchaudit (bt); + fprintf(stderr, "finished latch mgr audit\n"); + break; + case 'w': fprintf(stderr, "started indexing for %s\n", args->infile); if( in = fopen (args->infile, "rb") ) @@ -1894,8 +2133,9 @@ FILE *in; if( args->num == 1 ) sprintf((char *)key+len, "%.9d", 1000000000 - line), len += 9; + else if( args->num ) - sprintf((char *)key+len, "%.9d", line+args->idx * args->num), len += 9; + sprintf((char *)key+len, "%.9d", line + args->idx * args->num), len += 9; if( bt_insertkey (bt, key, len, 0, line, *tod) ) fprintf(stderr, "Error %d Line: %d\n", bt->err, line), exit(0); @@ -1915,8 +2155,9 @@ FILE *in; line++; if( args->num == 1 ) sprintf((char *)key+len, "%.9d", 1000000000 - line), len += 9; + else if( args->num ) - sprintf((char *)key+len, "%.9d", line+args->idx * args->num), len += 9; + sprintf((char *)key+len, "%.9d", line + args->idx * args->num), len += 9; if( bt_deletekey (bt, key, len, 0) ) fprintf(stderr, "Error %d Line: %d\n", bt->err, line), exit(0); @@ -1936,8 +2177,9 @@ FILE *in; line++; if( args->num == 1 ) sprintf((char *)key+len, "%.9d", 1000000000 - line), len += 9; + else if( args->num ) - sprintf((char *)key+len, "%.9d", line+args->idx * args->num), len += 9; + sprintf((char *)key+len, "%.9d", line + args->idx * args->num), len += 9; if( bt_findkey (bt, key, len) ) found++; @@ -1972,10 +2214,17 @@ FILE *in; fprintf(stderr, "started reading\n"); do { - bt_lockpage (bt, page_no, BtLockRead, &page); + if( bt->pool = bt_pinpool (bt, page_no) ) + page = bt_page (bt, bt->pool, page_no); + else + break; + bt->set = bt_pinlatch (bt, page_no); + bt_lockpage (BtLockRead, bt->set); cnt += page->act; next = bt_getid (page->right); - bt_unlockpage (bt, page_no, BtLockRead); + bt_unlockpage (BtLockRead, bt->set); + bt_unpinlatch (bt->set); + bt_unpinpool (bt->pool); } while( page_no = next ); cnt--; // remove stopper key @@ -2018,7 +2267,7 @@ BtDb *bt; fprintf (stderr, " where page_bits is the page size in bits\n"); fprintf (stderr, " mapped_segments is the number of mmap segments in buffer pool\n"); fprintf (stderr, " seg_bits is the size of individual segments in buffer pool in pages in bits\n"); - fprintf (stderr, " line_numbers set to 1 to append line numbers to input lines\n"); + fprintf (stderr, " line_numbers = 1 to append line numbers to keys\n"); fprintf (stderr, " src_file1 thru src_filen are files of keys separated by newline\n"); exit(0); } @@ -2036,7 +2285,7 @@ BtDb *bt; poolsize = atoi(argv[4]); if( !poolsize ) - fprintf (stderr, "Warning: mapped_pool has no segments\n"); + fprintf (stderr, "Warning: no mapped_pool\n"); if( poolsize > 65535 ) fprintf (stderr, "Warning: mapped_pool > 65535 segments\n");