Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Changes In Branch faster-memory-barrier Excluding Merge-Ins
This is equivalent to a diff from 1d21295707 to df66fec9bc
|
2019-02-08
| ||
| 22:34 | Small performance improvement and size reduction for pageFindSlot() - the routine in btree.c that locates a free slot for a cell on a btree page. (check-in: 1969372ac7 user: drh tags: trunk) | |
| 20:55 | Use a fast compiler-provided memory barrier exclusively, if such a memory barrier is available. (Leaf check-in: df66fec9bc user: drh tags: faster-memory-barrier) | |
| 17:28 | Further simplifications to sqlite3VdbeMemSetStr(). (check-in: 1d21295707 user: drh tags: trunk) | |
| 15:59 | Change the sqlite3VdbeMemGrow() routine so that it no longer guarantees a minimum size of 32 bytes. That minimum is no longer required, and without the extra check for the minimum size, the routine runs faster. (check-in: 5c499da8a4 user: drh tags: trunk) | |
Changes to src/mutex_unix.c.
| ︙ | |||
89 90 91 92 93 94 95 96 97 98 99 100 101 102 | 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 | + |
** where SQLite is compiled without mutexes.
*/
void sqlite3MemoryBarrier(void){
#if defined(SQLITE_MEMORY_BARRIER)
SQLITE_MEMORY_BARRIER;
#elif defined(__GNUC__) && GCC_VERSION>=4001000
__sync_synchronize();
# define sqlite3MemoryBarrier_IS_RELIABLE 1
#endif
}
/*
** Initialize and deinitialize the mutex subsystem.
*/
static int pthreadMutexInit(void){ return SQLITE_OK; }
|
| ︙ |
Changes to src/mutex_w32.c.
| ︙ | |||
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 | 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 | + + |
** compiled without mutexes (SQLITE_THREADSAFE=0).
*/
void sqlite3MemoryBarrier(void){
#if defined(SQLITE_MEMORY_BARRIER)
SQLITE_MEMORY_BARRIER;
#elif defined(__GNUC__)
__sync_synchronize();
# define sqlite3MemoryBarrier_IS_RELIABLE 1
#elif MSVC_VERSION>=1300
_ReadWriteBarrier();
# define sqlite3MemoryBarrier_IS_RELIABLE 1
#elif defined(MemoryBarrier)
MemoryBarrier();
#endif
}
/*
** Initialize and deinitialize the mutex subsystem.
|
| ︙ |
Changes to src/os_unix.c.
| ︙ | |||
4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 | 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 | + + |
sqlite3_file *fd /* Database file holding the shared memory */
){
UNUSED_PARAMETER(fd);
sqlite3MemoryBarrier(); /* compiler-defined memory barrier */
assert( fd->pMethods->xLock==nolockLock
|| unixFileMutexNotheld((unixFile*)fd)
);
#ifndef sqlite3MemoryBarrier_IS_RELIABLE
unixEnterMutex(); /* Also mutex, for redundancy */
unixLeaveMutex();
#endif
}
/*
** Close a connection to shared-memory. Delete the underlying
** storage if deleteFlag is true.
**
** If there is no shared memory associated with the connection then this
|
| ︙ |
Changes to src/os_win.c.
| ︙ | |||
4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185 | 4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185 4186 4187 | + + |
** any load or store begun after the barrier.
*/
static void winShmBarrier(
sqlite3_file *fd /* Database holding the shared memory */
){
UNUSED_PARAMETER(fd);
sqlite3MemoryBarrier(); /* compiler-defined memory barrier */
#ifndef sqlite3MemoryBarrier_IS_RELIABLE
winShmEnterMutex(); /* Also mutex, for redundancy */
winShmLeaveMutex();
#endif
}
/*
** This function is called to obtain a pointer to region iRegion of the
** shared-memory associated with the database file fd. Shared-memory regions
** are numbered starting from zero. Each shared-memory region is szRegion
** bytes in size.
|
| ︙ |