|
Problem IT40074
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Status: Closed |
MISSING READ-AHEAD IN RSS UNDERGOING LOGICAL LOG RESTORE
|
| product: |
INFORMIX SERVER / 5725A3900 / E10 - |
| Problem description: |
An RSS having to receive logical logs from log restore rather
than from primary might perform poorly due to missing
read-ahead.
Reason is an RSS read-ahead optimization moving the read-ahead
from bld_logrecs thread to RSS_Recv thread which, during log
restore, is in wait state, so would not see any log records and
not submit any read-ahead requests.
You can verify non-existing read-ahead be 'onstat -g rah'
returning empty read-ahead statistics. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* Users of Informix Server prior to 14.10.xC8. *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to Informix Server 14.10.xC8. *
**************************************************************** |
| Local Fix: |
Workaround, for the duration of the log restore:
onmode -wf CDR_FEATURES NORAOPT
After log restore completed, when logs are being received from
primary, re-enable the optimization using
onmode -wf CDR_FEATURES RAOPT |
| Solution |
|
| Workaround |
****************************************************************
* USERS AFFECTED: *
* Users of Informix Server prior to 14.10.xC8. *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to Informix Server 14.10.xC8. *
**************************************************************** |
| Comment |
Fixed in Informix Server 14.10.xC8. |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 25.02.2022
08.04.2022
08.04.2022 |
| Problem solved at the following versions (IBM BugInfos) |
|
| Problem solved according to the fixlist(s) of the following version(s) |
