[Bioclusters] requesting help for computational server setup (PE 4600)

[Joe Landman]

On Wed, 2003-09-17 at 15:57, Aaron Darling wrote:
> I would suggest taking your disks out of RAID 0.  See:
> http://www.storagereview.com/php/tiki/tiki-index.php?page=SingleDriveVsRaid0

This review isn't all that helpful to the informatics folks though. 
Many of the codes I have seen are limited by large block sequential
reads, which the article indicates to be one of the strengths of RAID0.

> The other FAQs at storage review may be worth your time as well.
> To summarize:  RAID 0 has decreased reliability over a single drive.

That is true.  Damage to a single disk will affect your file system on
other disks.

> Despite having increased sequential transfer rates, non-sequential access
> patterns (e.g. server/multi-user usage) are better for data distributed
> across two independent drives than with RAID 0 in general.  If you insist
> on RAID, you should sacrifice capacity and do RAID 1, buying you increased
> reliability, better seek times than RAID 0, and equivalent transfer rates
> to RAID 0 (assuming you've got a decent controller).

There are specific business cases for RAID 0, 1, 1+0, 3, and 5.  I do
agree that multiple spindles are good, but most applications are not
smart enough to break their data in a balanced manner across multiple
disks.  RAID 0 hides the pain of doing that from the programmer and puts
it into the OS.  You get specific benefits in specific cases.  You also
accept a higher risk.

> 
> -Aaron
> 
> 
> On Wed, 17 Sep 2003, karthik viswanathan wrote:
> 
> >
> > We have a PowerEdge 4600 server running RedHat 9. The system spec is given below.
> >
> > Server Specs:
> >
> > Dell PowerEdge 4600
> > Intel Xeon 2800 MHz Processor
> > 4096 MB ECC DDR Ram
> > 512 Cache
> > 2 x 146 GB SCSI hard disks (RAID 0)
> > OS : RedHat 9 (kernel 2.4.20-8), file system - ext3
> >
> > The main usage of this server is for bioinformatics computational work. Clients
> > run search/match C or C++ programs on this server through protocols like ssh.
> > The no of clients will be not more than 4. This server is also acting as a file
> > server for the same clients. T Get 3 newhe performance is not satisfactory so we
> > are planning to do some modification in the configuration. One of our plan is
> > promote a client workstation(dell precision-340, 1.5 GHz & 1GB ram) to a file
> > server and switch the two SCSI hard disk from the PowerEdge server to this
> > workstation. Add 3 new SCSI hard disk (37 GB) to the PowerEdge server and set a
> > RAID 0, if possible also add a second identical processor to the server.
> >
> > We are interested to know if this will improve the performance of the
> > computational server. Also it would be helpful if you could suggest any other
> > alternatives for improving the computational performance for bioinformatics
> > work. If any of you have poweredge 4600 please share your experience and ur
> > system configuration. Suggestions on disk partitioning, kernel and file system
> > to use will also be helpful
> >
> > Thanks for your time and help
> > Karthik
> >
> >
> > PS: We are more interested to improve the computational power than file handling!
> >
> >
> >
> >
> >
> >
> > _______________________________________________
> > Bioclusters maillist  -  Bioclusters@bioinformatics.org
> > https://bioinformatics.org/mailman/listinfo/bioclusters
> >
> _______________________________________________
> Bioclusters maillist  -  Bioclusters@bioinformatics.org
> https://bioinformatics.org/mailman/listinfo/bioclusters
-- 
Joseph Landman, Ph.D
Scalable Informatics LLC,
email: landman@scalableinformatics.com
web  : http://scalableinformatics.com
phone: +1 734 612 4615