Thread: RE: AW: AW: AW: WAL does not recover gracefully from ou t-of -dis k-sp ace
RE: AW: AW: AW: WAL does not recover gracefully from ou t-of -dis k-sp ace
From
"Mikheev, Vadim"
Date:
> > So seems we can use O_DSYNC without losing log write performance > > comparing with write() + fsync. Though, we didn't tested write() + > > fdatasync() yet... > > Good point, we should check fdatasync() too --- although I have no > machines where it's different from fsync(). I've tested it on Solaris - not better than O_DSYNC (expected, taking in account that O_DSYNC results don't depend on block counts). Ok, I've made changes in xlog.c and run tests: 50 clients inserted (int4, text[1-256]) into 50 tables, -B 16384, -wal_buffers 256, -wal_files 0. FSYNC: 257tps O_DSYNC: 333tps Just(?) 30% faster, -:( But I had no ability to place log on separate disk, yet... Vadim
"Mikheev, Vadim" <vmikheev@SECTORBASE.COM> writes: > Ok, I've made changes in xlog.c and run tests: Could you send me your diffs? regards, tom lane
Re: AW: AW: AW: WAL does not recover gracefully from ou t-of -dis k-sp ace
From
"Vadim Mikheev"
Date:
> > Ok, I've made changes in xlog.c and run tests: > > Could you send me your diffs? Sorry, Monday only. Vadim