Re: [parisc-linux] New 53c700 driver preformance evaluation

[Grant Grundler <grundler@puffin.external.hp.com>]

Daniel Engstrom wrote:
> Which is what I saw even if it was not very clearly expressed.
> I got ~400k/s better block throughput with the old driver with disconnects
> disabled (due to some driver problem) than with the new driver.

ah ok. It wasn't obvious to me.

> > BTW, another HPUX (only on workstations) thing is to set WCE (write
> > cache enable) on the SCSI device. 
> Can this behaviur be controlled? I use 10.20.

yes. iirc, it via scsictl command.

# scsictl
Usage: scsictl [-akq] [-m mode[=value]]... [-c command]... device

But HPUX calls WCE something else: "Immediate Reporting".
Keep that in mind when reading the man page.

> Another thing which I want to bring up is locking. It seems out getc() perfor
>   mance is stuck at 314chars/sec while HPUX gives almost 600, could it be
> that HPUX lock primitive is twice as fast as ours?

I think the lock primitive is the same - it's "ldcw".
It's something in the libc/syscall path but I have no clue what.

grant