diff options
| author | Thomas Munro | 2020-08-01 11:39:36 +0000 |
|---|---|---|
| committer | Thomas Munro | 2020-08-01 12:23:35 +0000 |
| commit | e2b37d9e7cabc90633c4bd822e1bcfdd1bda44c4 (patch) | |
| tree | f6cb217ead9b6e235c312ef2d4e2b53ec1716b9e | |
| parent | 022350b8495a8a7ff0ff8dd6791572e91e7cd6fe (diff) | |
Use pg_pread() and pg_pwrite() in slru.c.
This avoids lseek() system calls at every SLRU I/O, as was
done for relation files in commit c24dcd0c.
Reviewed-by: Ashwin Agrawal <aagrawal@pivotal.io>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA%2BhUKG%2Biqke4uTRFj8D8uEUUgj%2BRokPSp%2BCWM6YYzaaamG9Wvg%40mail.gmail.com
Discussion: https://postgr.es/m/CA%2BhUKGJ%2BoHhnvqjn3%3DHro7xu-YDR8FPr0FL6LF35kHRX%3D_bUzg%40mail.gmail.com
| -rw-r--r-- | src/backend/access/transam/slru.c | 25 |
1 files changed, 4 insertions, 21 deletions
diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c index 61249f4a12d..9e145f1c36a 100644 --- a/src/backend/access/transam/slru.c +++ b/src/backend/access/transam/slru.c @@ -669,7 +669,7 @@ SlruPhysicalReadPage(SlruCtl ctl, int pageno, int slotno) SlruShared shared = ctl->shared; int segno = pageno / SLRU_PAGES_PER_SEGMENT; int rpageno = pageno % SLRU_PAGES_PER_SEGMENT; - int offset = rpageno * BLCKSZ; + off_t offset = rpageno * BLCKSZ; char path[MAXPGPATH]; int fd; @@ -699,17 +699,9 @@ SlruPhysicalReadPage(SlruCtl ctl, int pageno, int slotno) return true; } - if (lseek(fd, (off_t) offset, SEEK_SET) < 0) - { - slru_errcause = SLRU_SEEK_FAILED; - slru_errno = errno; - CloseTransientFile(fd); - return false; - } - errno = 0; pgstat_report_wait_start(WAIT_EVENT_SLRU_READ); - if (read(fd, shared->page_buffer[slotno], BLCKSZ) != BLCKSZ) + if (pg_pread(fd, shared->page_buffer[slotno], BLCKSZ, offset) != BLCKSZ) { pgstat_report_wait_end(); slru_errcause = SLRU_READ_FAILED; @@ -749,7 +741,7 @@ SlruPhysicalWritePage(SlruCtl ctl, int pageno, int slotno, SlruFlush fdata) SlruShared shared = ctl->shared; int segno = pageno / SLRU_PAGES_PER_SEGMENT; int rpageno = pageno % SLRU_PAGES_PER_SEGMENT; - int offset = rpageno * BLCKSZ; + off_t offset = rpageno * BLCKSZ; char path[MAXPGPATH]; int fd = -1; @@ -862,18 +854,9 @@ SlruPhysicalWritePage(SlruCtl ctl, int pageno, int slotno, SlruFlush fdata) } } - if (lseek(fd, (off_t) offset, SEEK_SET) < 0) - { - slru_errcause = SLRU_SEEK_FAILED; - slru_errno = errno; - if (!fdata) - CloseTransientFile(fd); - return false; - } - errno = 0; pgstat_report_wait_start(WAIT_EVENT_SLRU_WRITE); - if (write(fd, shared->page_buffer[slotno], BLCKSZ) != BLCKSZ) + if (pg_pwrite(fd, shared->page_buffer[slotno], BLCKSZ, offset) != BLCKSZ) { pgstat_report_wait_end(); /* if write didn't set errno, assume problem is no disk space */ |