Subject | Strange DB Stats for a live DB |
---|---|
Author | Jason Chapman (JAC2) |
Post date | 2002-07-24T12:29:58Z |
Here's one for the Guru's,
This DB server was performing badly and on doing the dbstats the client
received the following.
IB bizarre Stats.....
Oldest TX: 794334 (OTX)
Oldest Active: 794335 (OITX)
Snapshot: 794274 (OSH)
Next: 1139198 (NT)
We normally disable sweep, but for this DB they had left it at 20K
Observations:
1) OSH < OITX, OSH < OTX - how can this be. This contradicts my
understanding, I would expect the numbers to go in ascending order OTX,
OITX, OSH, NT.
2) in this case would the sweep be continuous, i.e. when one sweep finishes
another is spawned because a sweep is not moving OIT forward, therefore NT
is always > OITX + 20K.
Thoughts, guesses and absolutes welcome, please.
Cheers,
Jason Chapman
JAC2 Consultancy
Training - Development - Consultancy
Delphi, InterBase, Firebird, OOAD, Development lifecycle assistance,
Troubleshooting projects, QA.....
www: When I get round to it....
Mob: (+44) 07966 211 959 (preferred)
Tel: (+44) 01928 751088
This DB server was performing badly and on doing the dbstats the client
received the following.
IB bizarre Stats.....
Oldest TX: 794334 (OTX)
Oldest Active: 794335 (OITX)
Snapshot: 794274 (OSH)
Next: 1139198 (NT)
We normally disable sweep, but for this DB they had left it at 20K
Observations:
1) OSH < OITX, OSH < OTX - how can this be. This contradicts my
understanding, I would expect the numbers to go in ascending order OTX,
OITX, OSH, NT.
2) in this case would the sweep be continuous, i.e. when one sweep finishes
another is spawned because a sweep is not moving OIT forward, therefore NT
is always > OITX + 20K.
Thoughts, guesses and absolutes welcome, please.
Cheers,
Jason Chapman
JAC2 Consultancy
Training - Development - Consultancy
Delphi, InterBase, Firebird, OOAD, Development lifecycle assistance,
Troubleshooting projects, QA.....
www: When I get round to it....
Mob: (+44) 07966 211 959 (preferred)
Tel: (+44) 01928 751088