Re: [Networker] Slow restores with Domino transaction logging

Our saveset for this system is just "NOTES:" (no quotes).  The schedule 
specifies a Full backup on Monday with Incrementals Tuesday through 
Friday.  We also had a very large incremental when the first one ran. 
However, we found this was because we had transaction logging turned on 
for a while before enabling the incremental backups.  That first 
incremental grabbed all of the existing transaction logs, not just the 
logs that existed since the last full backup.  After that first backup, 
the incrementals are about 12% of the size of the full backups on average. 
 Transaction logs are properly purged from the system after the backup 
completes.

We've tried staging the data to disk, but it still takes forever to get 
through the recovery.  We think it's actually a problem with the way 
Domino reads through the transaction logs.  Each database gets assigned a 
special identifier for backups called a DBIID.  Each transaction for a 
given database is recorded in the transaction log along with that DBIID. 
When you go to recover from an incremental, Domino must read through all 
transaction logs since the last full searching for transactions with the 
same DBIID as the database being recovered.  It then applies that 
transaction to the DB.

Right now, we don't know if the problem is reading through many individual 
transaction logs or just the volume of transactions to iterate through. 
We're trying various combinations of transaction log file size and backup 
schedules to see what helps and what doesn't.

Jeff Mery - MCSE, MCP
National Instruments

-------------------------------------------------------------------------
"Allow me to extol the virtues of the Net Fairy, and of all the fantastic
dorks that make the nice packets go from here to there. Amen."
TB - Penny Arcade
-------------------------------------------------------------------------



katans <networker-forum AT BACKUPCENTRAL DOT COM> 
Sent by: EMC NetWorker discussion <NETWORKER AT LISTSERV.TEMPLE DOT EDU>
06/21/2007 06:34 AM
Please respond to
NETWORKER AT LISTSERV.TEMPLE DOT EDU


To
NETWORKER AT LISTSERV.TEMPLE DOT EDU
cc

Subject
Re: [Networker] Slow restores with Domino transaction logging






Hi Jeff,

Can you explain me (or send an email) about how you can use incremental 
backup based on trans logs? I had read admin guide for NML 3.0 and I 
succesful run a backup job for full. When I choise incr, he make a full 
again.
I edit that conf file but..
I enabled also trans logs in archive mode as is describe in manual.
Can you tell me which save set do you set up for backup and other 
parameters?

Regarding your problem I saw the same behavior on SQL recovery. When there 
are a lot of incrementals it takes too much to rewind tapes. FOr example 
if you have 2 incrementals, you can restore data PiT at a specific time 
between that 2 incr. This it takes too much (hours). 
If you have possibility try to use backup to disk and after that migrate 
to tapes (staging).

Regards,

Catalin SCARLET
Senior Storage Consultant
STAR STORAGE
8, Dimitrie Pompei Blvd, Feper Bldg, 1st floor
Bucharest, 020337, Romania
Phone: +(40)-21-2421346; ext. 283
Fax: +(40)-21-2421348
Mobile: (40) 743.354452 
E-mail: catalin.scarlet AT star-group DOT ro 
Web: www.star-storage.ro

+----------------------------------------------------------------------
|This was sent by catalin.scarlet AT star-group DOT ro via Backup Central.
|Forward SPAM to abuse AT backupcentral DOT com.
+----------------------------------------------------------------------

To sign off this list, send email to listserv AT listserv.temple DOT edu and 
type 
"signoff networker" in the body of the email. Please write to 
networker-request AT listserv.temple DOT edu if you have any problems with this 
list. You can access the archives at 
http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER


To sign off this list, send email to listserv AT listserv.temple DOT edu and 
type "signoff networker" in the body of the email. Please write to 
networker-request AT listserv.temple DOT edu if you have any problems with this 
list. You can access the archives at 
http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER