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Re: performance analysis producer_consumer.cc TEST_T5
- From: law at redhat dot com
- To: Will Cohen <wcohen at redhat dot com>
- Cc: Loren James Rittle <rittle at latour dot rsch dot comm dot mot dot com>, libstdc++ at gcc dot gnu dot org
- Date: Tue, 17 Feb 2004 09:30:44 -0700
- Subject: Re: performance analysis producer_consumer.cc TEST_T5
- Reply-to: law at redhat dot com
In message <4030DE6D.50607@redhat.com>, Will Cohen writes:
>I looked over the code a bit more. The tight loop that the code spends
>most of its time is the result of the size() operation. The code is
>counting the number of elements in the list. The size() operation for
>the list basically has to walk the linked list. The means of counting
>the number of objects in other containers don't have a size() operation
>that is O(n). The other size operations usually get a couple values,
>subtract, and scale the result. There are two possible reasons I can
>think of things going wrong with the list version as a result of the
>size() operation not being atomic:
Funny, a one of the customers you visited a couple weeks ago has complained
repeatedly about not having an efficient means to get the number of objects
on a list....
jeff