Re: [RFC] block layer support for DMA IOMMU bypass mode II

From: Grant Grundler <grundler@parisc-linux.org>
To: Andi Kleen <ak@suse.de>
Cc: Grant Grundler <grundler@parisc-linux.org>,
	davem@redhat.com, alan@lxorguk.ukuu.org.uk,
	James.Bottomley@SteelEye.com, axboe@suse.de, suparna@in.ibm.com,
	linux-kernel@vger.kernel.org, alex_williamson@hp.com,
	bjorn_helgaas@hp.com
Subject: Re: [RFC] block layer support for DMA IOMMU bypass mode II
Date: Tue, 29 Jul 2003 20:31:47 -0600	[thread overview]
Message-ID: <20030730023147.GA31757@dsl2.external.hp.com> (raw)
In-Reply-To: <20030728131513.5d4b1bd3.ak@suse.de>

On Mon, Jul 28, 2003 at 01:15:13PM +0200, Andi Kleen wrote:
> Run it with 100-500 users (reaim -f workfile... -s 100 -e 500 -i 100) 
> I tested with ext3 on a single SCSI disk.

andi, davem, jens,
sorry for the long delay. Here's the data for ZX1 using u320 HBA
(LSI 53c1030) and ST373453LC disk (running U160 IIRC).
If you need more runs on this config, please ask.

Executive summary: < %1 difference for this config.

I'd still like to try a 53c1010 but don't have any installed right now.
I suspect 53c1010 is alot less efficient at retrieving SG lists
and will see a bigger difference in perf.

One minor issue when starting re-aim-7, but not during the run:

reaim(343): floating-point assist fault at ip 4000000000017a81, isr 0000020000000008                                                                            
reaim(343): floating-point assist fault at ip 4000000000017a61, isr 0000020000000008

For the record, I retrieved source from:
    http://umn.dl.sourceforge.net/sourceforge/re-aim-7/reaim-0.1.8.tar.gz

This should be renamed to osdl-aim-7 (or something like that).
The name space collision is unfortunate and annoying.

hth,
grant

#define BIO_VMERGE_BOUNDARY     0 /* (ia64_max_iommu_merge_mask + 1) */
iota:/mnt# reaim -f /mnt/usr/local/share/reaim/workfile.new_dbase -s100 -e 500 -i 100

REAIM Workload
Times are in seconds - Child times from tms.cstime and tms.cutime

Num     Parent   Child   Child  Jobs per   Jobs/min/  Std_dev  Std_dev  JTI
Forked  Time     SysTime UTime   Minute     Child      Time     Percent 
100     110.25   12.67   206.35  5605.19    56.05      3.48     3.29     96   
200     219.07   25.56   411.93  5642.06    28.21      7.83     3.73     96   
300     327.59   38.23   615.83  5659.46    18.86      12.79    4.09     95   
400     436.66   51.19   821.30  5661.19    14.15      18.34    4.42     95   
500     548.21   65.76   1029.15 5636.54    11.27      23.34    4.47     95   
Max Jobs per Minute 5661.19
iota:/mnt#

#define BIO_VMERGE_BOUNDARY     (ia64_max_iommu_merge_mask + 1)                 

iota:/mnt# PATH=$PATH:/mnt/usr/local/bin       
iota:/mnt# reaim -f /mnt/usr/local/share/reaim/workfile.new_dbase -s100 -e 500 -i 100

REAIM Workload
Times are in seconds - Child times from tms.cstime and tms.cutime

Num     Parent   Child   Child  Jobs per   Jobs/min/  Std_dev  Std_dev  JTI
Forked  Time     SysTime UTime   Minute     Child      Time     Percent 
100     108.72   12.47   203.78  5684.17    56.84      4.46     4.32     95   
200     217.64   25.59   408.90  5679.16    28.40      8.65     4.16     95   
300     326.48   37.88   613.62  5678.81    18.93      13.80    4.44     95   
400     434.87   50.53   817.64  5684.46    14.21      17.40    4.18     95   
500     544.69   65.23   1022.92 5672.92    11.35      21.53    4.12     95   
Max Jobs per Minute 5684.46