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in reply to Increasing the write buffer

I'm having a hard time convincing myself that increasing the size of the writes would have any effect at all as the limiting factor is the number of dirty pages that the vm manager is willing to allow. Once the vm manager starts flushing dirty pages to free up pages, disk writes are going to become synchronous.


s//----->\t/;$~="JAPH";s//\r<$~~/;{s|~$~-|-~$~|||s |-$~~|$~~-|||s,<$~~,<~$~,,s,~$~>,$~~>,, $|=1,select$,,$,,$,,1e-1;print;redo}

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Re^2: Increasing the write buffer
by Anonymous Monk on Jun 22, 2008 at 22:44 UTC
    Looking back in the archives I found that the IO buffer can indeed be changed - however it requires a recompilation of perl.

    After modifying perlio.c and doubling the buffer size - what used to take 3 hours now only takes 2. I'll play with it some more to see what I can get out of it.

    Thanks for all your comments.