Re: droped out precise time calculations in src/interfaces/libpq/fe-connect.c - Mailing list pgsql-hackers

From Joe Conway
Subject Re: droped out precise time calculations in src/interfaces/libpq/fe-connect.c
Date
Msg-id 3DACFABE.5060005@joeconway.com
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In response to Re: droped out precise time calculations in src/interfaces/libpq/fe-connect.c  (Bruce Momjian <pgman@candle.pha.pa.us>)
Responses Re: droped out precise time calculations in src/interfaces/libpq/fe-connect.c  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-hackers
Bruce Momjian wrote:
> Yes, the new code has _three_ time() calls, rather than the old code
> that I think only had two.  I was going to mention it but I figured
> time() was a pretty light system call, sort of like getpid().
> 
> I needed the additional time() calls so the computation of remaining
> time was more accurate, i.e. we are not resetting the timer on a
> select() EINTR anymore.
> 
> Should I try to rework it?
> 

I tried two more runs of 10000, and the average is pretty steady at 0.0087. 
However the total range is a fair bit wider than I originally reported.

I added a forth time() call to see what the effect would be. It increased the 
average to 0.0089 (two runs of 10000 connects each), so I don't think the 
time() call explains the entire difference.

Not sure this is worth worrying about or not. I'd guess anyone serious about 
keeping connect time to a minimum uses some kind of connection pool or 
persistent connection anyway.

Joe




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