Raghu,
as you wrote it was already discussed on this list. In last thread we with
Paul confirmed both that ESS is a different beast. Very, very deep under
the covers of ESS there are really RAID-5 arrays. But the addtional layers
on top of them is making ESS better than nearly all RAID-1
implementations.
Data taken from ESS manuals - ESS is capable to feed the data at .... 1280
MB/s (yes, one 1,28 gigabytes per second) !!! And with new 800 model it is
even better.
So answer again is "it depends". Not all RAID-5 are created equal.
If you can afford ESS this is (IMO) the best answer for TSM.
Zlatko Krastev
IT Consultant
Raghu S <[EMAIL PROTECTED]>
Sent by: "ADSM: Dist Stor Manager" <[EMAIL PROTECTED]>
23.10.2002 07:30
Please respond to "ADSM: Dist Stor Manager"
To: [EMAIL PROTECTED]
cc:
Subject: Re: RAID5 in TSM
Paul,
keeping TSM database,log and disk storage pool on RAID5 degrades the
performance???
Regards
Raghu
"Seay, Paul"
<seay_pd@NAPT To: [EMAIL PROTECTED]
HEON.COM> cc:
Sent by: Subject: Re: RAID5 in TSM
"ADSM: Dist
Stor Manager"
<[EMAIL PROTECTED]
RIST.EDU>
10/22/2002
06:29 AM
Please
respond to
"ADSM: Dist
Stor Manager"
Are you running compression?
Paul D. Seay, Jr.
Technical Specialist
Naptheon Inc.
757-688-8180
-----Original Message-----
From: Raghu S [mailto:raghu@;COSMOS.DCMDS.CO.IN]
Sent: Tuesday, October 22, 2002 8:03 AM
To: [EMAIL PROTECTED]
Subject: RAID5 in TSM
Hi,
There was a lot of discussion on this topic before.But i am requesting TSM
gurus give their comments again.
The set up is like this.
TSM Server : Windows NT 4.0 SP6, TSM 5.1.0.0
392 MB memory, P III
Adaptech Ultra SCSI
Hard Disk : Internal Hardware RAID 5:
array A : 8.678GB * 3 : 17.356GB data and 8.678
GB
parity
array B : 35.003 GB * 3 : 70.006GB data and
35.003
GB parity.
Both array A and array B are connected to the same channel.
OS and TSM 5.1 are installed on array A
TSM data base, recovery log and Disk storage pool are installed in array
B.
Database : 2GB+2GB = 4 GB and mirrored at TSM level on the same array
Recovery Log : 500MB + 500 MB = 1 GB and mirrored at TSM level on the same
array
Disk Storage pool : 10GB+10GB+10GB+10GB+5GB=45GB on array B
TSM client: 4.1.2.12 ( Tivoli says 4.1.2.12 is not supported with 5.1
Server. But i could take the backup,archive and restore with this
combination )
Number of Clients : 55, all are windows
Incremental backup : 1GB/ client/day.
backup window : 9AM to 6PM with 50% randamization ( all are in polling
mode
)
LAN : 100Mbps
End of the day only 10 clients could finish the backup.Remaining all are
missing or "?" ( in progress ) or failed.
Through the entire backup window the CPU load is 100% with dsmsvc.exe
holding 98%
I tested with various options. I stopped the schedular and fired 3 clients
backup manually at the same time.Each client has 1 GB of incremental data.
It took three hours to finish the backup. While backing up i observed
there
was lot of idletime outs of sessions.
Network choke is not there. I checked this with FTP.
Whats the bottleneck here? Is RAID 5 is creating problems ( DB,log and
storage pool all are on the RAID 5 )? I asked the customer to arrange a
testing machine without any RAID. I will be getting that in two
days.Before
going on to the testing i like to know your comments on this.
Regards
Raghu S Nivas
Consultant - TSM
DCM Data Systems Ltd
New Delhi
India.
