paulhorn/sqlite
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Defer the exclusive db lock until the pager cache is flushed to disk. 41

Browse Source 
tests now fail. (CVS 1528)

FossilOrigin-Name: d2f69e5ef2f261a00bb8427a4e2a1638ecfd17a9
This commit is contained in:
danielk1977
2004-06-04 10:38:30 +00:00
parent 24162fe668
commit 9eed505701
5 changed files with 84 additions and 68 deletions
Download Patch File Download Diff File Expand all files Collapse all files
manifest
+8 -8
View File
@@ -1,5 +1,5 @@
C Move\sthe\s'busy-callback'\slogic\sto\sthe\spager\slayer.\s(CVS\s1527)
D 2004-06-04T06:22:01
C Defer\sthe\sexclusive\sdb\slock\suntil\sthe\spager\scache\sis\sflushed\sto\sdisk.\s41\ntests\snow\sfail.\s(CVS\s1528)
D 2004-06-04T10:38:30
F Makefile.in ab7b0d5118e2da97bac66be8684a1034e3500f5a
F Makefile.linux-gcc b86a99c493a5bfb402d1d9178dcdc4bd4b32f906
F README f1de682fbbd94899d50aca13d387d1b3fd3be2dd
@@ -39,15 +39,15 @@ F src/insert.c 4268d9e3959cc845ea243fb4ec7507269404dad9
F src/legacy.c ad23746f15f67e34577621b1875f639c94839e1f
F src/main.c 4e8e5c96e5a9460e71b97c83cb30cb3ad44db259
F src/md5.c 4302e84ae516c616bb079c4e6d038c0addb33481
F src/os.h cc2fd62b2e8e11103701913871908ff77532af58
F src/os.h 4e480eb92737ebcdd1e1136bdbf5cd22223bd1b4
F src/os_common.h 744286a27de55c52f1b18921e8d17abbf7fafc0f
F src/os_mac.c b823874690615ace0dd520d3ad1fe8bfd864b7e0
F src/os_mac.h 51d2445f47e182ed32d3bd6937f81070c6fd9bd4
F src/os_unix.c 3175540f8d1c820dab7a470c50875c221c3a98cd
F src/os_unix.c a4feb70b23fa5272f53cd2c74588484b54294800
F src/os_unix.h 7999f2246c6347707e98f7078871ea8ca605df3f
F src/os_win.c 92b51a38437b98d8aa3ac05b57c71e1d1092e5be
F src/os_win.h 5d41af24caaef6c13a2d8e2399caa1c57d45c84d
F src/pager.c 00fabe423729e8d8a4c5e8f9602341b69a5a21b5
F src/pager.c 944f6b071279887574081281f27bb2af88b42905
F src/pager.h 0c7b5ac45c69e690c45d160d03bdc8fbd2d4657b
F src/parse.y 27c1ce09f9d309be91f9e537df2fb00892990af4
F src/pragma.c 1b58d852b84b36a8b84e2245dd29b63c377414ec
@@ -214,7 +214,7 @@ F www/support.tcl 1801397edd271cc39a2aadd54e701184b5181248
F www/tclsqlite.tcl 19191cf2a1010eaeff74c51d83fd5f5a4d899075
F www/vdbe.tcl 59288db1ac5c0616296b26dce071c36cb611dfe9
F www/whentouse.tcl a8335bce47cc2fddb07f19052cb0cb4d9129a8e4
P d57e5252c8baaf615c2cd218a33356ea5d95a5e2
R 2d675c6973e7ef6b1853da4802084a3d
P ff70b6d2b60c143e3ada0606ceff97571998c7e3
R 0c89db702f37cfc005476b7d72917d3b
U danielk1977
Z bb8854c6d118151a9229d93a5653a12b
Z 2dc315e5203a158a5157a45199e1dfe1
manifest.uuid
+1 -1
View File
@@ -1 +1 @@
ff70b6d2b60c143e3ada0606ceff97571998c7e3
d2f69e5ef2f261a00bb8427a4e2a1638ecfd17a9
src/os.h
+1
View File
@@ -84,6 +84,7 @@
** The following values may be passed as the second argument to
** sqlite3OsLock().
*/
#define NO_LOCK 0
#define SHARED_LOCK 1
#define RESERVED_LOCK 2
#define PENDING_LOCK 3
src/os_unix.c
-24
View File
@@ -641,30 +641,6 @@ int sqlite3OsFileSize(OsFile *id, off_t *pSize){
return SQLITE_OK;
}
/*
** Change the status of the lock on the file "id" to be a readlock.
** If the file was write locked, then this reduces the lock to a read.
** If the file was read locked, then this acquires a new read lock.
**
** Return SQLITE_OK on success and SQLITE_BUSY on failure. If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsReadLock(OsFile *id){
return sqlite3OsLock(id, SHARED_LOCK);
}
/*
** Change the lock status to be an exclusive or write lock. Return
** SQLITE_OK on success and SQLITE_BUSY on a failure. If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsWriteLock(OsFile *id){
return sqlite3OsLock(id, EXCLUSIVE_LOCK);
}
/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, return
src/pager.c
+74 -35
View File
@@ -18,7 +18,7 @@
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.111 2004/06/04 06:22:01 danielk1977 Exp $
** @(#) $Id: pager.c,v 1.112 2004/06/04 10:38:31 danielk1977 Exp $
*/
#include "os.h" /* Must be first to enable large file support */
#include "sqliteInt.h"
@@ -522,7 +522,7 @@ static int pager_unwritelock(Pager *pPager){
}else{
assert( pPager->dirtyFile==0 || pPager->useJournal==0 );
}
rc = sqlite3OsReadLock(&pPager->fd);
rc = sqlite3OsLock(&pPager->fd, SHARED_LOCK);
if( rc==SQLITE_OK ){
pPager->state = SQLITE_READLOCK;
}else{
@@ -658,15 +658,28 @@ static int pager_delmaster(const char *zMaster){
*/
OsFile journal;
int nMaster;
off_t jsz;
rc = sqlite3OsOpenReadOnly(zJournal, &journal);
sqliteFree(zJournal);
if( rc!=SQLITE_OK ){
sqlite3OsClose(&journal);
sqliteFree(zJournal);
goto delmaster_out;
}
sqlite3OsClose(&journal);
/* Check if the file is big enough to be a format 3 journal file
** with the required master journal name. If not, ignore it.
*/
rc = sqlite3OsFileSize(&journal, &jsz);
if( rc!=SQLITE_OK ){
sqlite3OsClose(&journal);
goto delmaster_out;
}
if( jsz<(sizeof(aJournalMagic3)+4*sizeof(u32)+strlen(zMaster)+1) ){
sqlite3OsClose(&journal);
continue;
}
/* Seek to the point in the journal where the master journal name
** is stored. Read the master journal name into memory obtained
** from malloc.
@@ -1532,9 +1545,40 @@ static int syncJournal(Pager *pPager, const char *zMaster){
static int pager_write_pagelist(PgHdr *pList){
Pager *pPager;
int rc;
int busy = 1;
if( pList==0 ) return SQLITE_OK;
pPager = pList->pPager;
/* At this point there may be either a RESERVED or EXCLUSIVE lock on the
** database file. If there is already an EXCLUSIVE lock, the following
** calls to sqlite3OsLock() are no-ops.
**
** The upgrade from a RESERVED to PENDING lock cannot return SQLITE_BUSY,
** unless someone is not following the locking protocol.
**
** The upgrade from PENDING to EXCLUSIVE can return SQLITE_BUSY. It's
** not totally clear that the busy-callback should be invoked here
** though. (?)
*/
rc = sqlite3OsLock(&pPager->fd, PENDING_LOCK);
if( rc==SQLITE_BUSY ){
return SQLITE_PROTOCOL;
}
if( rc!=SQLITE_OK ){
return rc;
}
do {
rc = sqlite3OsLock(&pPager->fd, EXCLUSIVE_LOCK);
}while( rc==SQLITE_BUSY &&
pPager->pBusyHandler &&
pPager->pBusyHandler->xFunc &&
pPager->pBusyHandler->xFunc(pPager->pBusyHandler->pArg, "", busy++)
);
if( rc!=SQLITE_OK ){
return rc;
}
while( pList ){
assert( pList->dirty );
sqlite3OsSeek(&pPager->fd, (pList->pgno-1)*(off_t)SQLITE_PAGE_SIZE);
@@ -1607,20 +1651,15 @@ int sqlite3pager_get(Pager *pPager, Pgno pgno, void **ppPage){
*/
if( pPager->nRef==0 && !pPager->memDb ){
int busy = 1;
while( busy ){
rc = sqlite3OsReadLock(&pPager->fd);
if( rc==SQLITE_BUSY &&
pPager->pBusyHandler &&
pPager->pBusyHandler->xFunc &&
pPager->pBusyHandler->xFunc(pPager->pBusyHandler->pArg, "", busy++)
){
rc = SQLITE_OK;
}else{
busy = 0;
}
if( rc!=SQLITE_OK ){
return rc;
}
do {
rc = sqlite3OsLock(&pPager->fd, SHARED_LOCK);
}while( rc==SQLITE_BUSY &&
pPager->pBusyHandler &&
pPager->pBusyHandler->xFunc &&
pPager->pBusyHandler->xFunc(pPager->pBusyHandler->pArg, "", busy++)
);
if( rc!=SQLITE_OK ){
return rc;
}
pPager->state = SQLITE_READLOCK;
@@ -1906,7 +1945,7 @@ static int pager_open_journal(Pager *pPager){
sqlite3pager_pagecount(pPager);
pPager->aInJournal = sqliteMalloc( pPager->dbSize/8 + 1 );
if( pPager->aInJournal==0 ){
sqlite3OsReadLock(&pPager->fd);
sqlite3OsLock(&pPager->fd, SHARED_LOCK);
pPager->state = SQLITE_READLOCK;
return SQLITE_NOMEM;
}
@@ -1914,7 +1953,7 @@ static int pager_open_journal(Pager *pPager){
if( rc!=SQLITE_OK ){
sqliteFree(pPager->aInJournal);
pPager->aInJournal = 0;
sqlite3OsReadLock(&pPager->fd);
sqlite3OsLock(&pPager->fd, SHARED_LOCK);
pPager->state = SQLITE_READLOCK;
return SQLITE_CANTOPEN;
}
@@ -2020,20 +2059,20 @@ int sqlite3pager_begin(void *pData, int nMaster){
pPager->origDbSize = pPager->dbSize;
}else{
int busy = 1;
while( busy ){
rc = sqlite3OsWriteLock(&pPager->fd);
if( rc==SQLITE_BUSY &&
pPager->pBusyHandler &&
pPager->pBusyHandler->xFunc &&
pPager->pBusyHandler->xFunc(pPager->pBusyHandler->pArg, "", busy++)
){
rc = SQLITE_OK;
}else{
busy = 0;
}
if( rc!=SQLITE_OK ){
return rc;
}
do {
/* If the library grabs an EXCLUSIVE lock here, as in the commented
** out line, then it exhibits the old locking behaviour - a writer
** excludes all readers, not just other writers.
*/
/* rc = sqlite3OsLock(&pPager->fd, EXCLUSIVE_LOCK); */
rc = sqlite3OsLock(&pPager->fd, RESERVED_LOCK);
}while( rc==SQLITE_BUSY &&
pPager->pBusyHandler &&
pPager->pBusyHandler->xFunc &&
pPager->pBusyHandler->xFunc(pPager->pBusyHandler->pArg, "", busy++)
);
if( rc!=SQLITE_OK ){
return rc;
}
pPager->nMaster = nMaster;
pPager->state = SQLITE_WRITELOCK;
@@ -2515,7 +2554,7 @@ int sqlite3pager_stmt_begin(Pager *pPager){
assert( pPager->journalOpen );
pPager->aInStmt = sqliteMalloc( pPager->dbSize/8 + 1 );
if( pPager->aInStmt==0 ){
sqlite3OsReadLock(&pPager->fd);
sqlite3OsLock(&pPager->fd, SHARED_LOCK);
return SQLITE_NOMEM;
}
#ifndef NDEBUG