Re: Performance Improvement by reducing WAL for Update Operation

On 7/9/13 12:09 AM, Amit Kapila wrote:
> I think the first thing to verify is whether the results posted can be validated in some other environment setup by another person.
> The testcase used is posted at below link:
> http://www.postgresql.org/message-id/51366323.8070606@vmware.com

That seems easy enough to do here, Heikki's test script is excellent.
The latest patch Hari posted on July 2 has one hunk that doesn't apply
anymore now. Inside src/backend/utils/adt/pg_lzcompress.c the patch
tries to change this code:

- if (hent)
+ if (hentno != INVALID_ENTRY)

But that line looks like this now:

if (hent != INVALID_ENTRY_PTR)

Definitions of those:

#define INVALID_ENTRY 0
#define INVALID_ENTRY_PTR (&hist_entries[INVALID_ENTRY])

I'm not sure if different error handling may be needed here now due the
commit that changed this, or if the patch wasn't referring to the right
type of error originally.

--
Greg Smith 2ndQuadrant US greg(at)2ndQuadrant(dot)com Baltimore, MD
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