Really slow named pipes

Duane Clark dclark at akamail.com
Sat Aug 23 19:31:38 CDT 2003


This is a bit old, from May, but anyhow...

The patch to implement anonymous pipes on top of named pipes:
http://www.winehq.com/hypermail/wine-cvs/2003/05/0305.html
along with a corresponding bug fix:
http://www.winehq.com/hypermail/wine-cvs/2003/06/0123.html
causes Xilinx ISE to run really, really slow.

It has a window to which messages are sent via a pipe, and what I see 
now is that one line comes out every 2/3 of a second or so, as regular 
as a clock at least by eye. I can revert those two patches, and it goes 
back to spitting out the messages very fast. Since there are a lot of 
messages being sent, the current version slows the app down to a crawl.

It does not look like the patch itself is the problem; I am guessing 
that it is the underlying named pipe implementation that is the problem, 
which was exposed by the patch.

Also, reverting to the full CVS 5/20, just after the pipe patches, has 
the same problem. So it appears that whatever is wrong with named pipes 
(if that really is the problem) was already there on 5/20, rather than 
it being something introduced since then.

Any hints on what I could look for would be welcome.





More information about the wine-devel mailing list