Subject Re: [firebird-support] High CPU use after restore
Author setysvar

Den 28.10.2015 20:56, skrev Jardar Maatje jardar.maatje@... [firebird-support]:
Hi again

A bit more details. I found the query the slows this down and it is a query that includes blob data. If I adjust the query to cast the blob to varchar first the query executes 30 timers faster. I will try to change my queries to fix this.

However I still wonder why this suddenly became a problem after restoring the database.

Best regards

Jardar is a report of a 60-time improvement (from half a minute to half a second) with Firebird 2.5.2/2.5.3 and Jaybird 2.2.5/2.1.6 when changing from blob to varchar, I guess this could be the same problem as you observe.

Could it be that your original database had never before been restored with Firebird 2.5.1, but only with an older Firebird/InterBase version (or never restored, but created with an older Firebird/InterBase version)? If so, then you may have been protected against this particular bug (I'm just guessing, I don't know if older versions have it or not), as well as the bug (only existing in 2.5.1, 2.5.0 and 2.5.2 are OK) that I warned about earlier today regarding indexes containing more than one field (which - I think - can give you wrong results from some queries).