Re: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-12 Thread Tom Lane
"Mikheev, Vadim" <[EMAIL PROTECTED]> writes: > Probably we should update XLogWrite to write() more than 1 block, > but Tom should apply his patches first (btw, did you implement > "log file size" condition for checkpoints, Tom?). Yes I did. There's a variable now to specify a checkpoint every N

RE: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-12 Thread Mikheev, Vadim
> > FSYNC:257tps > > O_DSYNC: 333tps > > > > Just(?) 30% faster, -:( > > First of all, if you ask me, that is one hell of an improvement :-) Of course -:) But tfsync tests were more promising -:) Probably we should update XLogWrite to write() more than 1 block, but Tom should ap

Re: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-10 Thread Vadim Mikheev
> > Ok, I've made changes in xlog.c and run tests: > > Could you send me your diffs? Sorry, Monday only. Vadim ---(end of broadcast)--- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]

Re: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-10 Thread Tom Lane
Denis Perchine <[EMAIL PROTECTED]> writes: > On Saturday 10 March 2001 08:41, Tom Lane wrote: >> More numbers, these from a Powerbook G3 laptop running Linux 2.2: > Eeegghhh. Sorry... But where did you get O_DSYNC on Linux? > bits/fcntl.h: # define O_DSYNC O_SYNC Hm, must be. Okay, so

Re: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-09 Thread Denis Perchine
On Saturday 10 March 2001 08:41, Tom Lane wrote: > More numbers, these from a Powerbook G3 laptop running Linux 2.2: Eeegghhh. Sorry... But where did you get O_DSYNC on Linux? Maybe here? bits/fcntl.h: # define O_DSYNC O_SYNC There is no any O_DSYNC in the kernel... Even in the latest

Re: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-09 Thread Tom Lane
"Mikheev, Vadim" <[EMAIL PROTECTED]> writes: > Ok, I've made changes in xlog.c and run tests: Could you send me your diffs? regards, tom lane ---(end of broadcast)--- TIP 1: subscribe and unsubscribe commands go to [EMAIL P

RE: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-09 Thread Mikheev, Vadim
> > 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 o

Re: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-09 Thread Tom Lane
"Mikheev, Vadim" <[EMAIL PROTECTED]> writes: >> $ gcc -Wall -O -DINIT_WRITE -DUSE_DSYNC -DBLOCKS=1 tfsync.c > ^^^ > You should use -DUSE_OSYNC to test O_SYNC. Ooops ... let's hear it for cut-and-paste, and for sharp-eyed readers! Just for completeness, here

RE: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-09 Thread Mikheev, Vadim
> Starting to look like we should just use ODSYNC where available, and > forget about dumping more per write ... I'll run these tests on RedHat 7.0 tomorrow. Vadim ---(end of broadcast)--- TIP 2: you can get off all lists at once with the unregist

Re: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-09 Thread Tom Lane
More numbers, these from a Powerbook G3 laptop running Linux 2.2: [tgl@g3 tmp]$ uname -a Linux g3 2.2.18-4hpmac #1 Thu Dec 21 15:16:15 MST 2000 ppc unknown [tgl@g3 tmp]$ gcc -Wall -O -DINIT_WRITE -DUSE_DSYNC -DBLOCKS=1 tfsync.c [tgl@g3 tmp]$ time ./a.out real0m32.418s user0m0.020s sys

RE: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-09 Thread Mikheev, Vadim
> $ gcc -Wall -O -DINIT_WRITE -DUSE_DSYNC -DBLOCKS=1 tfsync.c ^^^ You should use -DUSE_OSYNC to test O_SYNC. So you've tested N * write() + fsync(), exactly what I've asked -:) > So I also see that there is no benefit to writing more than > one block at a ti

Re: AW: AW: AW: [HACKERS] WAL does not recover gracefully from ou t-of -dis k-sp ace

2001-03-09 Thread Tom Lane
"Mikheev, Vadim" <[EMAIL PROTECTED]> writes: > Tom, could you run this test for different block sizes? > Up to 32*8k? >> >> You mean changing the amount written per write(), while holding the >> total file size constant, right? > Yes. Currently XLogWrite writes 8k blocks one by one. From what I'