Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
| Comment: | Do not use the Linux mremap() call. Use the same strategy for xMremap() as on OSX instead. |
|---|---|
| Downloads: | Tarball | ZIP archive | SQL archive |
| Timelines: | family | ancestors | descendants | both | experimental-mmap |
| Files: | files | file ages | folders |
| SHA1: | 5ed8ad780c991d2ca44003ee84350fb5e95ad58e |
| User & Date: | dan 2013-03-21 14:47:47 |
Context
|
2013-03-21
| ||
| 15:57 | Fix a problem when opening a write-transaction while there exist read-only b-tree cursors in mmap mode. check-in: 32e0bbb7 user: dan tags: experimental-mmap | |
| 14:47 | Do not use the Linux mremap() call. Use the same strategy for xMremap() as on OSX instead. check-in: 5ed8ad78 user: dan tags: experimental-mmap | |
|
2013-03-20
| ||
| 18:25 | Optimize the xMremap method in os_unix.c some. check-in: 9529ed88 user: dan tags: experimental-mmap | |
Changes
Changes to src/os_unix.c.
4474 4475 4476 4477 4478 4479 4480 4481 4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 |
/* According to some sources, the effect of changing the size of the ** underlying file on mapped regions that correspond to the added or ** removed pages is undefined. However, there is reason to believe that ** on modern platforms like Linux or OSX, things just work. For example, ** it is possible to create a mapping larger than the file on disk and ** extend the file on disk later on. ** ** Exploit this on OSX to reduce the number of munmap()/mmap() calls ** if the file size is changing. In this case all mappings are rounded ** up to the nearest 4MB. And if a new mapping is requested that has the ** same rounded size as an old mapping, the old mapping can simply be ** reused as is. ** ** It would be possible to do the above on Linux too. However, Linux has ** the non-standard mremap() call to resize existing mappings, which can ** be used instead. */ #if defined(__APPLE__) nNewRnd = ROUNDUP(nNew, 4096*1024); nOldRnd = ROUNDUP(nOld, 4096*1024); #else nNewRnd = ROUNDUP(nNew, 4096*1); nOldRnd = ROUNDUP(nOld, 4096*1); #endif /* On OSX or Linux, reuse the old mapping if it is the right size. */ #if defined(__APPLE__) || defined(__linux__) if( nNewRnd==nOldRnd ){ return SQLITE_OK; } #endif /* On Linux, if there is both an old and new mapping, resize the old ** mapping using the non-standard mremap() call. */ #if defined(_GNU_SOURCE) && defined(__linux__) if( nNewRnd && nOldRnd ){ void *pOld = *ppMap; *ppMap = pNew = mremap(pOld, nOldRnd, nNewRnd, MREMAP_MAYMOVE); if( pNew==MAP_FAILED ){ *ppMap = 0; return SQLITE_IOERR_MREMAP; } return SQLITE_OK; } #endif /* If we get this far, unmap any old mapping. */ if( nOldRnd!=0 ){ void *pOld = *ppMap; |
| | | | | < < < < | < < < < < < < < < < < < < < |
4474 4475 4476 4477 4478 4479 4480 4481 4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 |
/* According to some sources, the effect of changing the size of the ** underlying file on mapped regions that correspond to the added or ** removed pages is undefined. However, there is reason to believe that ** on modern platforms like Linux or OSX, things just work. For example, ** it is possible to create a mapping larger than the file on disk and ** extend the file on disk later on. ** ** Exploit this on Linux and OSX to reduce the number of munmap()/mmap() ** calls required if the file size is changing. In this case all mappings ** are rounded up to the nearest 4MB. And if a new mapping is requested ** that has the same rounded size as an old mapping, the old mapping can ** be reused as is. */ #if defined(__APPLE__) || defined(__linux__) nNewRnd = ROUNDUP(nNew, 4096*1024); nOldRnd = ROUNDUP(nOld, 4096*1024); #else nNewRnd = ROUNDUP(nNew, 4096*1); nOldRnd = ROUNDUP(nOld, 4096*1); #endif /* On OSX or Linux, reuse the old mapping if it is the right size. */ #if defined(__APPLE__) || defined(__linux__) if( nNewRnd==nOldRnd ){ return SQLITE_OK; } #endif /* If we get this far, unmap any old mapping. */ if( nOldRnd!=0 ){ void *pOld = *ppMap; |