Yes, it does no harm to switch to ROLLFORWARD mode in mid-stream, it just
works.
It does fire an extra DB backup; or maybe that's when you switch BACK from
ROLLFORWARD to NORMAL, I forget.
The amount of log space you need depends on the amount of activity rather
than the DB size, so it's hard to say whether 2 GB is enough log space or
not. You should be OK if you have a trigger set, just keep an eye on the
log utilization for a few days.
-----Original Message-----
From: Gill, Geoffrey L. [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, April 17, 2001 11:07 AM
To: [EMAIL PROTECTED]
Subject: Roll Forward Mode
Here is a little of my environment that might help answer this question:
TSM 4.1.2
AIX 4.3.3
3494lib with 4 3590-E1A's
Database:
Available Space (MB): 18,000
Assigned Capacity (MB): 18,000
Maximum Extension (MB): 0
Maximum Reduction (MB): 8,740
Page Size (bytes): 4,096
Total Usable Pages: 4,608,000
Used Pages: 2,356,088
Pct Util: 51.1
Max. Pct Util: 51.5
Physical Volumes: 6
Buffer Pool Pages: 32,768
Total Buffer Requests: 188,336,528
Cache Hit Pct.: 98.12 (BufPoolSize 131072)
Cache Wait Pct.: 0.00
Backup in Progress?: No
Type of Backup In Progress:
Incrementals Since Last Full: 0
Changed Since Last Backup (MB): 621.21
Percentage Changed: 6.75
Last Complete Backup Date/Time: 04/16/01 11:16:22
Log:
Available Space (MB): 2,000
Assigned Capacity (MB): 2,000
Maximum Extension (MB): 0
Maximum Reduction (MB): 1,996
Page Size (bytes): 4,096
Total Usable Pages: 511,488
Used Pages: 279
Pct Util: 0.1
Max. Pct Util: 89.3
Physical Volumes: 4
Log Pool Pages: 2,048
Log Pool Pct. Util: 0.18
Log Pool Pct. Wait: 0.00
Cumulative Consumption (MB): 409,183.96
Consumption Reset Date/Time: 09/27/99 13:00:44
I want to switch to roll forward mode but am not sure if the log size is
sufficient. Does anyone have any experience with switching in mid stream? I
have about 120 clients, I do have a space trigger set for both the DB and
log.
I'd also like to know if anyone thinks my (BufPoolSize 131072) is a
bit low. I discovered my cache hit was down below 97% last week so I reset
the buffer pool and it creeped up to just over 98%. Would increasing this
help? Do I need to consider my total server memory before I increase this?
Thanks for all the help,
Geoff Gill
TSM Administrator
NT Systems Support Engineer
SAIC
E-Mail: [EMAIL PROTECTED]
Phone: (858) 826-4062
Pager: (888) 997-9614
