Re: [Libvir] Patch to make reading of HTTP response more efficient
On Thu, Mar 30, 2006 at 03:51:06PM +0100, Daniel P. Berrange wrote:
When processing the header of HTTP responses from Xend, libvirt
currently
reads data a single byte at a time. Since its using lowlevel UNIX read()
function there is no buffering, which results in a large number of system
calls. The attached patch re-factors the code so that it reads data in
4k chunks whenever possible. Since most rsponses are < 4k in size processing
the response now only takes two read() syscalls, rather than several hundred.
Right, good optimization ! Applied, I just reindented and cleaned a bit,
it's commited in CVS, thanks a lot !
Of course most (90%) of the CPU overhead is still on the
Xend/XenStored
end of the channel, but that's out of our control until the XML-RPC API
comes along.
There is a awful lot of things that can be done to optimize, like
keeping the connection alive, trying to do minimal caching,that we
really didn't try to address yet. At this point this is more about
functionalities than getting optimal, but this will come :-)
Daniel
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Daniel Veillard | Red Hat http://redhat.com/
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