| /* src/include/port/linux.h */ | |
| /* | |
| * As of July 2007, all known versions of the Linux kernel will sometimes | |
| * return EIDRM for a shmctl() operation when EINVAL is correct (it happens | |
| * when the low-order 15 bits of the supplied shm ID match the slot number | |
| * assigned to a newer shmem segment). We deal with this by assuming that | |
| * EIDRM means EINVAL in PGSharedMemoryIsInUse(). This is reasonably safe | |
| * since in fact Linux has no excuse for ever returning EIDRM; it doesn't | |
| * track removed segments in a way that would allow distinguishing them from | |
| * private ones. But someday that code might get upgraded, and we'd have | |
| * to have a kernel version test here. | |
| */ | |
| /* | |
| * Set the default wal_sync_method to fdatasync. With recent Linux versions, | |
| * xlogdefs.h's normal rules will prefer open_datasync, which (a) doesn't | |
| * perform better and (b) causes outright failures on ext4 data=journal | |
| * filesystems, because those don't support O_DIRECT. | |
| */ | |