Re: [HACKERS] [PATCHES] Trivial patch to double vacuum speed on tables with no indexes

2006-09-04 Thread Alvaro Herrera
Gregory Stark wrote: Bruce Momjian [EMAIL PROTECTED] writes: Tom Lane wrote: Bruce Momjian [EMAIL PROTECTED] writes: Patch applied. Thanks. Wait a minute. This patch changes the behavior so that LockBufferForCleanup is applied to *every* heap page, not only the ones where

Re: [HACKERS] [PATCHES] Trivial patch to double vacuum speed on tables with no indexes

2006-09-04 Thread Tom Lane
Bruce Momjian [EMAIL PROTECTED] writes: Patch applied. Thanks. Wait a minute. This patch changes the behavior so that LockBufferForCleanup is applied to *every* heap page, not only the ones where there are removable tuples. It's not hard to imagine scenarios where that results in severe

Re: [HACKERS] [PATCHES] Trivial patch to double vacuum speed on tables with no indexes

2006-09-04 Thread Gregory Stark
Bruce Momjian [EMAIL PROTECTED] writes: Tom Lane wrote: Bruce Momjian [EMAIL PROTECTED] writes: Patch applied. Thanks. Wait a minute. This patch changes the behavior so that LockBufferForCleanup is applied to *every* heap page, not only the ones where there are removable tuples.

Re: [HACKERS] [PATCHES] Trivial patch to double vacuum speed on tables with no indexes

2006-08-28 Thread Gregory Stark
Tom Lane [EMAIL PROTECTED] writes: The reason the patch is so short is that it's a kluge. If we really cared about supporting this case, more wide-ranging changes would be needed (eg, there's no need to eat maintenance_work_mem worth of RAM for the dead-TIDs array); and a decent respect to

Re: [HACKERS] [PATCHES] Trivial patch to double vacuum speed on tables with no indexes

2006-08-28 Thread Alvaro Herrera
Gregory Stark wrote: Tom Lane [EMAIL PROTECTED] writes: The reason the patch is so short is that it's a kluge. If we really cared about supporting this case, more wide-ranging changes would be needed (eg, there's no need to eat maintenance_work_mem worth of RAM for the dead-TIDs

Re: [HACKERS] [PATCHES] Trivial patch to double vacuum speed on tables with no indexes

2006-08-27 Thread Tom Lane
stark [EMAIL PROTECTED] writes: There isn't really any need for the second pass in lazy vacuum if the table has no indexes. How often does that case come up in the real world, for tables that are large enough that you'd care about vacuum performance? regards, tom lane

Re: [HACKERS] [PATCHES] Trivial patch to double vacuum speed on tables with no indexes

2006-08-27 Thread Gregory Stark
Tom Lane [EMAIL PROTECTED] writes: stark [EMAIL PROTECTED] writes: There isn't really any need for the second pass in lazy vacuum if the table has no indexes. How often does that case come up in the real world, for tables that are large enough that you'd care about vacuum performance?

Re: [HACKERS] [PATCHES] Trivial patch to double vacuum speed on tables with no indexes

2006-08-27 Thread Tom Lane
Gregory Stark [EMAIL PROTECTED] writes: Tom Lane [EMAIL PROTECTED] writes: How often does that case come up in the real world, for tables that are large enough that you'd care about vacuum performance? I would have had the same objection if it resulted in substantially more complex code but