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Subject Killer malloc() in apr_sendv()
Date Fri, 17 Aug 2001 17:14:41 GMT
In a message dated 01-08-17 16:02:41 EDT, you write:

> > I know the conventional wisdom is that SSI is slow because of
>  > the malloc calls in bucket creation, but the problem might
>  > be elsewhere.  I've tried adding in a free list of recycled
>  > buckets, to reduce the calls to malloc, but it didn't seem to
>  > affect performance measurably.
>  I've replaced the malloc/frees in the bucket code on Windows with a power 
> 2 allocator
>  and it makes a BIG difference in performance. I expect the same on every 
> with the
>  exception of Linux.

You might want to add the same 'power of 2' stuff to a call 
that is absolutely killing the windows version.

apr_sendv() in /srclib/apr/network_io/win32/sendrecv.c
is using a malloc()/free() combo for only 8 bytes!
It's using WSASend() and can 'scatter gather' but so far
I've never seen more than 2 separate buffers to 'gather'
on any particular call to apr_sendv().

There is a comment there about 'putting it on the stack' but
you'd be better off doing this sooner than later because
the malloc()/free() for only 8 bytes is killing you on every

Kevin Kiley

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