Should I Compress My Catalog

[Randy_Samora]

Enquiring minds want to know.
Windows environment One Master (only a master, nothing else), 5 Media Servers, another 5 SAN Media servers, very few requests for restores and the catalog now stands at 200GB. Should I compress it? What do I gain besides disk space and a faster catalog backup? What do I lose?

My main goal is the faster catalog backup but I don't want to lose a lot of NetBackup response time in the process. I was going to ask about catalog backups but I'll open another thread.

Thanks,
Randy

[Stumpr2]

Randy,
I compress everything that is over 14 days old. This value is determined by the type of restores that are generally requested. Normally a user will request a restore from the last full and the subsequent incrementals. I've used this philosophy for almost a decade and it has worked fine for me.
Bob

[Randy_Samora]

Bob,

Does compressing the catalog add response time to any of NetBackup's other functions? If restores, which have to go into the compressed data, take longer because the data is compressed, that's no big deal to me because I don't do very many restores. But are there any other NB functions or utilities that will suffer if I compress the catalog?

Thanks for the response(s),
Randy

[Stumpr2]

The only delay I have seen has to do with querying the catalog for information via bpimagelist, bplist or the GUI for file information. The actual restore time is not effected, just the setup time. You could even set the compress time to 31 days so that monthly fulls will still be available.

But....
Please be advised that
NT File System (NTFS) compression of VERITAS NetBackup catalog or log directories may negatively affect performance.
http://seer.support.veritas.com/docs/245926.htm

Details:
NetBackup performance can be negatively affected on NetBackup systems on which NTFS compression is enabled for the NetBackup catalog or log directories. This is because writes and reads require that the data be compressed and decompressed as an operation of the processor, prior to the required disk I/O being performed.

As a result, while NTFS compression may be enabled for the volumes on which NetBackup stores its log and database files, these directories (specifically, \NetBackup\logs, \NetBackup\db and \volmgr\db) and all sub-directories and files should not have NTFS compression enabled.

Microsoft Technet article Q251186 (http://www.microsoft.com ), entitled "Best Practices for NTFS Compression" states that "Heavily loaded servers with considerable write traffic are poor candidates for data compression." This accurately describes a NetBackup system performing backups. The article goes on to state, "Programs that use transaction logging and constantly write to a database or log should not store their files on a compressed volume."

If compression is needed on the NetBackup catalogs due to size, it is recommended that NetBackup catalog compression be enabled to compress catalogs during database cleanup operations (rather than concurrent with the backup). This option can be set within the Configure NetBackup interface by opening the properties of the master server, navigating to the Global NetBackup Attributes tab, checking the "Compress catalog after:" checkbox and specifying how many days should transpire before an image is compressed.

Note: Catalog compression will decrease performance when browsing for restores.

[Randy_Samora]

Bob to the rescue again. If you're ever in the neighborhood, stop by and we'll talk shop over dinner.

Thanks again,
Randy

[MOIMOI]

Hi Bob,

Compression is one way to down size the catalog folder and as per the recommendation it wil affect the performance.

I need to know is there any other way i can down size the catalog. It is over 8 GB for me now and i want to bring down.

Does image clean up down size the expired data, coz our retention period is 1 month.

Cheers,

A

[Stumpr2]

Compressing the catalog for images older than 1 week will probably not decrease the performance. Most restores are requested from the last full backup. Most people do weekly full backups and daily incremental backups. See my first reply in this thread.

Your catalog is already extremely small. I suggest adding more disk space. Then it will appear smaller :)

Image cleanup does delete expired images as well as compresses images according to the compress attribute.

One many times overlooked item to decrease the catalog size is using the exclude_lists. The catalog size is determined by the number of files, not the size of the files.Consider excluding man pages, fonts, and any other repetitive files across your backup environment. It isn't much for a single server, but when you multiply that by fifty servers??