Re: Faster StrNCpy

Tom,

Yes, the clients are using the V3 protocol and prepared statements.

David

________________________________

From: Tom Lane [mailto:tgl(at)sss(dot)pgh(dot)pa(dot)us]
Sent: Mon 10/2/2006 2:09 PM
To: Strong, David
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: [HACKERS] Faster StrNCpy

"Strong, David" <david(dot)strong(at)unisys(dot)com> writes:
> Obviously, different copy mechanisms suit different data sizes. So, I
> added a little debug to the strlcpy () function that was added to
> Postgres the other day. I ran a test against Postgres for ~15 minutes
> that used 2 client backends and the BG writer - 8330804 calls to
> strlcpy () were generated by the test.

> Out of the 8330804 calls, 6226616 calls used a maximum copy size of
> 2213 bytes e.g. strlcpy (dest, src, 2213) and 2104074 calls used a
> maximum copy size of 64 bytes.

> I know the 2213 size calls come from the set_ps_display () function. I
> don't know where the 64 size calls come from, yet.

Prepared-statement and portal hashtable lookups, likely. Were your
clients using V3 extended query protocol?

regards, tom lane