RE: Logical logs

I hope you have LBU_PRESERVE set to 1. I personally have no qualms with having more than enough space dedicated to logical logs. The amount of money spent on extra disk space is easily saved by not having a database locked exclusively to rollback long transactions, especially if you run out of log space. I personally would never change the long transaction high water marks. I don't like getting woken up in the middle of the night and being told the database is hung... Will >===== Original Message From Girish Punjabi <girishpunjabi@my-deja.com> ===== >HI Vinodh, > >Nothing wrong with more logical logs except that is is inefficient from >an administrative point of view. >Instead of having 120 logical logs of 2MB each you can have 30 logs of >8MB each.You can also set LTXHWM & LTXEHWM are 80 and 90 >respectively.We have overcome the long transaction problem here by >deviating from Informix suggested values of 50 and 60. >Also , as William suggested, you need to have a look at the code as >well , as no amount of tuning can help if the code is inefficient. > > >In article <8ge25v$s64$1@news.xmission.com>, > William Rice <ricew@operamail.com> wrote: >> >> I do not feel their is anything wrong with having that many logical >logs. >> One thing you might want to establish is why you are having long >transactions >> and whether or not what is being done is required to be one >transaction. >> >> If the cause is a process which is required to be updated in one >transaction >> you have no choice but to increase the number of logs. >> >> If the cause of the long transactions is a purge or something of that >nature, >> which can be done in smaller increments without effecting the >validity of the >> data, you might want to look into making the purge use a select cursor >> and deleting each record and committing periodically.(If their is a >better way >> to do this I would love to hear it.) If you just increase the number >of logs, >> as >> the amount of data purged grows, the likelihood of hitting a long >transaction >> again grows. A program which commits at regular intervals bypasses >> these emergencies. >> >> If the cause of the long transactions is a lock held for an >inordinate period >> of time, it might be worth implementing some sort of timing mechanism >> to cause the user to abort after holding a lock for some period of >time, >> or rewriting the application to not hold locks while waiting for user >input. >> >> Hope this helps, >> Will >> >===== Original Message From "Vinod Bhansali" <iiug@hotmail.com> ===== >> >In our system, I am noticing Long Transactions being caused >sometimes. We >> >have 80 log files, each of size 2048. LTXHWM & LTXEHWM are 50 & 60. >I don't >> >want to increase them. I am planning to increase the no. of log >files to 120 >> >or to 160. Are there any pros and cons of having more no. of logical >log >> >files. We have continuous logical log backup running and we take >zero level >> >db backup daily using ontape. >> > >> >Thanks in advance >> >Vinod Bhansali >> >>_______________________________________________________________________ >_ >> >Get Your Private, Free E-mail from MSN Hotmail at >http://www.hotmail.com >> >> ------------------------------------------------------------ >> This e-mail has been sent to you courtesy of OperaMail, as a free >service from >> Opera Software, makers of the award-winning Web Browser, Opera. >Visit us at >> http://www.opera.com/ or our portal at: http://www.myopera.com/ Your >free e-mail >> account is waiting at: http://www.operamail.com/ >> ------------------------------------------------------------ >> >> > > >Sent via Deja.com http://www.deja.com/ >Before you buy. ------------------------------------------------------------ This e-mail has been sent to you courtesy of OperaMail, as a free service from Opera Software, makers of the award-winning Web Browser, Opera. Visit us at http://www.opera.com/ or our portal at: http://www.myopera.com/ Your free e-mail account is waiting at: http://www.operamail.com/ ------------------------------------------------------------