[HACKERS] Re: Checkpointer split has broken things dramatically (was Re: DELETE vs TRUNCATE explanation)

2012-07-24 Thread Greg Stark
On Wed, Jul 18, 2012 at 1:13 AM, Craig Ringer ring...@ringerc.id.au wrote: That makes me wonder if on top of the buildfarm, extending some buildfarm machines into a crashfarm is needed: - Keep kvm instances with copy-on-write snapshot disks and the build env on them - Fire up the VM, do a

Re: [HACKERS] Re: Checkpointer split has broken things dramatically (was Re: DELETE vs TRUNCATE explanation)

2012-07-18 Thread Tom Lane
Craig Ringer ring...@ringerc.id.au writes: On 07/18/2012 08:31 AM, Tom Lane wrote: Not sure if we need a whole farm, but certainly having at least one machine testing this sort of stuff on a regular basis would make me feel a lot better. OK. That's something I can actually be useful for.

[HACKERS] Re: Checkpointer split has broken things dramatically (was Re: DELETE vs TRUNCATE explanation)

2012-07-18 Thread Robert Haas
On Tue, Jul 17, 2012 at 6:56 PM, Tom Lane t...@sss.pgh.pa.us wrote: So I went to fix this in the obvious way (attached), but while testing it I found that the number of buffers_backend events reported during a regression test run barely changed; which surprised the heck out of me, so I dug

[HACKERS] Re: Checkpointer split has broken things dramatically (was Re: DELETE vs TRUNCATE explanation)

2012-07-17 Thread Craig Ringer
On 07/18/2012 06:56 AM, Tom Lane wrote: Robert Haas robertmh...@gmail.com writes: On Mon, Jul 16, 2012 at 3:18 PM, Tom Lane t...@sss.pgh.pa.us wrote: BTW, while we are on the subject: hasn't this split completely broken the statistics about backend-initiated writes? Yes, it seems to have done

Re: [HACKERS] Re: Checkpointer split has broken things dramatically (was Re: DELETE vs TRUNCATE explanation)

2012-07-17 Thread Tom Lane
Craig Ringer ring...@ringerc.id.au writes: On 07/18/2012 06:56 AM, Tom Lane wrote: This implies that nobody has done pull-the-plug testing on either HEAD or 9.2 since the checkpointer split went in (2011-11-01) That makes me wonder if on top of the buildfarm, extending some buildfarm

Re: [HACKERS] Re: Checkpointer split has broken things dramatically (was Re: DELETE vs TRUNCATE explanation)

2012-07-17 Thread Craig Ringer
On 07/18/2012 08:31 AM, Tom Lane wrote: Not sure if we need a whole farm, but certainly having at least one machine testing this sort of stuff on a regular basis would make me feel a lot better. OK. That's something I can actually be useful for. My current qemu/kvm test harness control code