Perl slowness

[Noam Rathaus]

The only obvious one is that read() shown under strace, takes a significant
more time on the new machine than the old one

On Tue, Sep 8, 2009 at 5:43 PM, Shachar Shemesh <shachar at shemesh.biz> wrote:

>  Noam Meltzer wrote:
>
> the time output does looks like you have higher cpu usage for some reason,
> so i agree with Shachar on this.
>
> you can also try to pinpoint the place the cpu is spent.
> strace and/or ltrace with the '-f -c' flags can help.
>
> I'm not sure about ltrace, but strace will not help. Most of the time is
> spent in user space, not in the kernel.
>
> Strace may help if the problem is time spent in another process (i.e. -
> while the main process is sleeping), but it seems Noam has already tried
> that one and failed to spot any obvious candidates.
>
> Shachar
>
>
>
>
> On Tue, Sep 8, 2009 at 5:24 PM, Shachar Shemesh <shachar at shemesh.biz>wrote:
>
>>  Noam Rathaus wrote:
>>
>> I know the time difference doesn't look too bad, but take a bigger code
>> set:
>>
>> Fast:
>> real    0m1.682s
>> user    0m1.584s
>> sys    0m0.064s
>>
>> Slow:
>> real    0m16.730s
>> user    0m9.345s
>> sys    0m0.096s
>>
>>   These times spell "CPU intensive". Does your library do anything
>> special? If you try to import a dummy library, does this still happen?
>>
>> Shachar
>>
>> --
>> Shachar Shemesh
>> Lingnu Open Source Consulting Ltd.http://www.lingnu.com
>>
>>
>
>
> --
> Shachar Shemesh
> Lingnu Open Source Consulting Ltd.http://www.lingnu.com
>
>
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