Re: Inefficient bytea escaping?

Tom Lane wrote:
> Andreas Pflug <pgadmin(at)pse-consulting(dot)de> writes:
>
>>Here are the results, with the copy patch:
>
>
>>psql \copy 1.4 GB from table, binary:
>>8.0 8.1 8.2dev
>>36s 34s 36s
>
>
>>psql \copy 6.6 GB from table, std:
>>8.0 8.1 8.2dev
>>375s 362s 290s (second:283s)
>
>
> Hmph. There's something strange going on on your platform (what is it
> anyway?)

Debian 2.6.26.

> It's interesting (and surprising) that the runtime is
> actually less for psql \copy than for server COPY. This is a dual Xeon
> machine, maybe the frontend copy provides more scope to use both CPUs?

The dual CPU explanation sounds reasonable, but I found the same
tendency on a single 3GHz (HT disabled).
Strange observation using top:
user >90%, sys <10%, idle+wait 0% but only postmaster consumes cpu,
showing 35%, the rest neglectable.
>
> It would be interesting to see what's happening on your machine with
> oprofile or equivalent.

I'll investigate further, trying to find the missing CPU.

Regards,
Andreas