Re: [PATCHES] Trivial patch to double vacuum speed

Tom Lane wrote:
> Bruce Momjian <bruce@momjian.us> 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 system-wide performance degradation.
> Has there been any real-world testing of this idea?

I see the no-index case now:

+               if (nindexes)
+                       LockBuffer(buf, BUFFER_LOCK_SHARE);
+               else
+                       LockBufferForCleanup(buf);

Let's see what Greg says, or revert.

--
  Bruce Momjian   bruce@momjian.us
  EnterpriseDB    http://www.enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +