Helge Hafting wrote:
With nothing attached, any write to the serial device might go
through a lengthy timeout because of flow control. [...] But I can't
see why it'd make scsi disks slower. The scsi host adapter
initialization writes some messages of course, but there should be no
more console accesses during a hdparm test run.
This makes sense to me. When I attach a serial cable and use that to
login (I've got agetty running), hdparm produces no console messages
that I can see using minicom. Still, the disk throughput is around 1.5
MB/sec for some reason. When I disable the serial console in grub.conf
and reboot I get over 70 MB/sec again.
A combination of out-of-tree patches (mainly network related but also
one to disable PM_TIMERS) seem to eliminate the issue even with the
serial console enabled, at least for the moment. That means I no longer
have a problem, but the whole thing is mysterious to me.
Jeff
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
