maybe off topic but what is MAXPHYS set in compiled kernel?
every BSD flavor i've seen sets it way too low for modern drives.
2MB is smallest IMHO value that make sense on modern drives.
you may experience lots of seeking when reading 4 files from same disk
On Thu, 19 Jul 2012, David Diggles wrote:
On Thu, Jul 19, 2012 at 08:08:26AM +0200, Jan Stary wrote:
have you also tried -o 'Compression no'?
I have now. No real difference;
SSH Options: [-o Ciphers=arcfour -o Compression=no]
64.68132476895114469583 MB/s
63.56096147431307883010 MB/s
61.69097005503488103824 MB/s
61.41473507203868873527 MB/s
Data in the range of many terabytes, possibly up to petabytes are
expected to go over the link, so the hpn-ssh patch used by HPC sites
looks like the most viable for this - thanks, Michael.
Dan, yes the 4 ssh processes were at 100% cpu, I guess with the
encryption overhead. Both client and server are 8 core. There
was no other load at the time of testing, so half cores are
available to service disk and network load.
