Le 18 mars 2011 à 19:02, Christopher Faylor a écrit :


Or, are you saying that you still see failures when setting the buffer
size down to 64K?
With a buffer 64k all is fine.
With a buffer 31*1024*1024, that's different. It seems that
all pipes open at the same time add their buffers up to an upper limit (the nonpaged value)
which cannot be exceeded.

This also explains a failure i had this afternoon, on the CPU which was normally "non-failing": i launched 5 xz-compressions at the same time (not big ones, but you must know that xz-compression can be rather slow even on small files, so it is very likely that the 5 were concurrent); and 3 of them failed unexpectedly. I understand now that 5 open pipes at the same time would use 5*31*1024*1024 bytes, which is too much for a CPU that has nonpaged=98Mb as i said in my previous
message.

Now, i suppose that with a 64k buffer, you would not be able to exceed 98Mb/64kb=1568 open pipes at the
same time.

Denis Excoffier.



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