Huge speedup to wine ReadFile on small packets
tony_lambregts at telusplanet.net
Thu Nov 7 23:45:39 CST 2002
Hannu Kotipalo wrote:
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> The only program I use at windows on home is wzebra, a windows based reversi
>game (http://www.nada.kth.se/~gunnar/othello.html). (linux version coming,
>but it's binary only :-()
> Unfortunately current wine version needs over 10 minutes time to start the
>program! In windows, starting time is just a few seconds. I found out that
>the source of the delay was a database file (opening book file), which wzebra
>reads in by a few byte packets. Fortunately wzebra itself measures the time
>needed for the readout.
>Since wine has a lot of overhead for opening and closing unix filesystem for
>every packet, the delay is understandable (but not acceptable!).
>Of course, buffering helps. I made a Quick-and-dirty 1k buffer for just
>ReadFile - routine and database readout dropped from over 800 seconds down to
>12-13 seconds! (On my 200 Mhz Pentium Pro)
>I think this should be fixed in a more sophisticated way, so I did not yet
>post my patch. Also, this patch helps only on this particular problem;
>reading a file by small packets with ReadFile. However, I noticed that wzebra
>reads even bitmaps on byte by one... Don't know how usual this is, thought.
>In addition, I do not have too much time for playing with this. If someone is
>interested in continuing my work, please mail me, I can reply by sending the
Please submit the patch/hack to wine-patches for comments/review. I think that at least I would try the patch out, Since a speed up is always welcome.
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