Backup Central

Hi All,



I am trying to find Official IBM documentation that
explicitly answers the following questions:



1) How many TSM instances can be run per Linux Blade? ( I have been
told that there is a limit of one instance per Blade, but I don't see this
anywhere in the TSM 6.2 Server documentation)

2) Is there a limit to the number of files the a TSM client can back
up? ( I have found an unofficial document that specifies that TSM's HSM
product can handle about 100 Million files, but again I can't seem to locate
it in IBM's HSM documentation)

3) Lastly, with regard to TSM's underlying DB2 datbase, are there
significant issues with memory management? (I have checked the DB2 APARS
up to DB2 version 9.8 and there seem to be a number of fixes for things such
as memory leaks, but I do not know how many of those apply to TSM and how
many are from general DB2 usage)



Thanks in advance!



Jim Neal

Sr. TSM Administrator

U.C. Berkeley Storage and Backup Group

On 7 dec. 2011, at 20:35, Jim Neal wrote:

Hi All,



I am trying to find Official IBM documentation that
explicitly answers the following questions:



1) How many TSM instances can be run per Linux Blade? ( I have been
told that there is a limit of one instance per Blade, but I don't see this
anywhere in the TSM 6.2 Server documentation)

you'll probably run into memory issues eventually. There are no hard technical limitations that I know of, apart from TCP limits that you can have a maximum of 64510 processes listening on non-priviliged ports (1025 - 65535) on a single system (actually per IP-address unless the processes listen on 0.0.0.0 like TSM does). You'll probably not be able to fit enough memory or CPUs in your box to run all of those servers at any usable performance. I'd guess that with a wintel box more that 1 TB off RAM would be a challenge, so with say 20 GB of RAM for a single instance, you'll not be able to fit more that 50 instances based on the amount of RAM you'll need, and probably if you account for at least 2 CPU cores for an instance.


2) Is there a limit to the number of files the a TSM client can back
up? ( I have found an unofficial document that specifies that TSM's HSM
product can handle about 100 Million files, but again I can't seem to locate
it in IBM's HSM documentation)


Yes there is. I've been told that there is a hard limit on the number of files that a TSM server can have backed up in it's entire lifespan. I've never heard of anybody ever running into that limit. 6.3 has been tested for 4 TB databases, with about 500 bytes in the DB for each file, that would amount to 8,000 million files, if I'm not mistaking.

3) Lastly, with regard to TSM's underlying DB2 datbase, are there
significant issues with memory management? (I have checked the DB2 APARS
up to DB2 version 9.8 and there seem to be a number of fixes for things such
as memory leaks, but I do not know how many of those apply to TSM and how
many are from general DB2 usage)



Issues as in bugs? Or issues as in BD2 is happier with more memory? More is better for real life workloads....


Thanks in advance!



Jim Neal

Sr. TSM Administrator

U.C. Berkeley Storage and Backup Group

--
Met vriendelijke groeten/Kind Regards,

Remco Post
r.post < at > plcs.nl
+31 6 248 21 622

Depending on the client operation, you'll run out of address space if
you're on a platform for which IBM only distributes 32-bit BA clients
(i.e. x86 Linux). There's ways you can mitigate this (for instance,
virtual mount points, memory efficient backup option). We still run into
problems around 10-20 million files in a single operation though.

-- Skylar Thompson (skylar2 < at > u.washington.edu)
-- Genome Sciences Department, System Administrator
-- Foege Building S046, (206)-685-7354
-- University of Washington School of Medicine

On 12/ 7/11 11:35 AM, Jim Neal wrote:
2) Is there a limit to the number of files the a TSM client can back
up? ( I have found an unofficial document that specifies that TSM's HSM
product can handle about 100 Million files, but again I can't seem to locate
it in IBM's HSM documentation)