Subject Re: [firebird-support] Please help! Database stops responding after all users have been connected.
Author Andrew Guts
Helen Borrie wrote:

>At 03:16 PM 10/09/2004 +0300, you wrote:
>>Hi, all
>>I have a production system runs with firebird about 3 years. About week
>>ago the system's behaviour becamed very strange. Server almost stops
>>responding after N-th user have connected to the database. Suddenly
>>simple queries becames too heavy - execution time raises from
>>milliseconds to minutes. When it happens CPU load is extreme high on
>>first hardware and moderate on second (hardware configurations are
>>described below), system memory is not exhausted and HDD activity is low.
>>I've tried to check the database, backup/restore, upgrade Firebird from
>>1.5.0 to 1.5.1, switch from super to classic and back, migration to
>>another hardware - nothing helps. A few days ago server works before
>>hang about 3-4 hours. Now it takes a few minutes.
>>The system serves about 15-25 connections. The database size is about
>>350-400Mb, last year added about 100Mb.
>>Hardware: AMD Athlon XP3200+, 1.5Gb RAM, DPT Ultra-80 SCSI RAID 0 (3 x
>>9.1Gb HDD) + one standalone SCSI HDD for system boot, gigabit ethernet
>>controller, OS - Red Hat Linux 9.0 . I've tried another computer: Dual
>>Xeon 2.8 GHz, 2Gb RAM, 18Gb U160 SCSI HDD (10000RPM), gigabit ethernet
>>controller, OS - Fedora Core 1.
>>I suspect the following:
>>- the production database and security.fdb are descendants from beta
>>versions of Firebird 1.5 or even release 1.0 . But backup/restore of it
>>was not helped and ODS version is 10.1 now.
>>- My old, but simple UDFs stops working, but how they did work about 3
>>last years? And there are no server crashes. By the way it worked on the
>>same system at least from 1.5.0 release date (April or May)
>>- some fundamental OS limits have been reached.
>>And now the strangest thing: I've just replaced the HDD in the dual Xeon
>>system and installed the Firebird under W2003 Server there (affinity
>>mask was set to 15 in firebird.conf). The system is working excellent
>>under load already 4 hours.
>>Please help me to diagnose and solve the problem.
>Clearly you didn't have Red Hat 9.1 or Fedora Core 1 for the past three
Sure, but at least from RH9 release date. I've migrated from RH 7.2.
Fedora 1 was installed yesterday on fresh hardware.

> Best guess here is that NPTL threading is messing things up. See
>the Linux installation notes in the Firebird 1.5 release notes for
>instructions on disabling the NTPTL; or install the NPTL kit for Firebird.
And how about the same problem with Super 1.5.0 and Classic 1.5.1 ?