Re: Memory Performance Issue with Fedora Core 2 Kernels

[James Foris <james foris med ge com>]

Dave Mitchell wrote:
> Do you still get the slowdown if you mmap /dev/zero rather than your
> driver?

Forwarding the responce:

Transfers from /dev/zero -> /dev/shm are unreasonably high (e.g. 128.000 MB
in 0.000028 sec), which suggests that there isn't really any I/O going on
here.

Transfers from /dev/zero to disk are approximately 2x faster, but still
slow.  Instead of around 20MB/s it looks like around 40 MB/s.

John