Logical Log Configuration

Good Evening (well it is here in Scotland), I have a query regarding the size and number of logical logs. Until lately, we had around 80 users logging into our informix database and running various reports, updates etc. Unfortunately (?) we no longer have the same amount of users but we still require to maintain the database, and indeed, we need to update the database on a nightly basis from our legacy systems. For the last year or so a nightly cron job uploaded a comma delimited file containing around 6000 entries. This however in the last month has increased to around 20000 entries and is causing long transactions in the upload. So, the question is, what should I set the size and number of logical logs to ? Currently I have 24 logical logs each of size 2000. The logical logs sit in raw disk out of the rootdb space. onstat -d INFORMIX-OnLine Version 7.24.UC5 -- On-Line -- Up 3 days 01:24:05 --138808 Kbytes Dbspaces address number flags fchunk nchunks flags owner name c036100 1 1 1 1 N informix rootdbs c036978 2 1 2 1 N informix inflogs Chunks address chk/dbs offset size free bpages flags pathname c036170 1 1 0 50000 48913 PO- /dev/vx/rdsk/datadg/rootspac c0362b8 2 2 0 1005109 947056 PO- /dev/vx/rdsk/datadg/vol02 Regards David M MacAllister Securicor Omega International

david.mcallister@soi.co.uk wrote: > > Good Evening (well it is here in Scotland), > > I have a query regarding the size and number of logical logs. Until > lately, we had around 80 users logging into our informix database and > running various reports, updates etc. Unfortunately (?) we no longer have > the same amount of users but we still require to maintain the database, and > indeed, we need to update the database on a nightly basis from our legacy > systems. > > For the last year or so a nightly cron job uploaded a comma delimited file > containing around 6000 entries. This however in the last month has > increased to around 20000 entries and is causing long transactions in the > upload. > > So, the question is, what should I set the size and number of logical logs > to ? > > Currently I have 24 logical logs each of size 2000. The logical logs sit > in raw disk out of the rootdb space. > > onstat -d > INFORMIX-OnLine Version 7.24.UC5 -- On-Line -- Up 3 days 01:24:05 --> 138808 Kbytes > Dbspaces > address number flags fchunk nchunks flags owner name > c036100 1 1 1 1 N > informix rootdbs > c036978 2 1 2 1 N > informix inflogs > Chunks > address chk/dbs offset size free bpages flags pathname > c036170 1 1 0 50000 48913 > PO- /dev/vx/rdsk/datadg/rootspac > c0362b8 2 2 0 1005109 947056 PO- > /dev/vx/rdsk/datadg/vol02 > > Regards > > David M MacAllister > Securicor Omega International Hello David, why increasing the number or size of log files. If Your are only loading the data without doing updates or so, why don't use the dbload utility, where You can state the number of rows to load inside a single transaction? Wolfgang

1st Anyone with the name McAllister can't be all bad. 2nd Get your logs out of the rootdbs and into their own dbspace 3rd You can do a number of things. Add more logs (I use 20 of 5000 for my mix but that is purely a function of your own application), you can change the load to do shorter transactions, or you can change the LTXHWM parameter in theonconfig file. This parm is defaulted to 50%, but you can adjust that up if this is the only transaction that is running. Doug McAllister Fidelity Investments david.mcallister@soi.co.uk wrote: > Good Evening (well it is here in Scotland), > > I have a query regarding the size and number of logical logs. Until > lately, we had around 80 users logging into our informix database and > running various reports, updates etc. Unfortunately (?) we no longer have > the same amount of users but we still require to maintain the database, and > indeed, we need to update the database on a nightly basis from our legacy > systems. > > For the last year or so a nightly cron job uploaded a comma delimited file > containing around 6000 entries. This however in the last month has > increased to around 20000 entries and is causing long transactions in the > upload. > > So, the question is, what should I set the size and number of logical logs > to ? > > Currently I have 24 logical logs each of size 2000. The logical logs sit > in raw disk out of the rootdb space. > > onstat -d > INFORMIX-OnLine Version 7.24.UC5 -- On-Line -- Up 3 days 01:24:05 --> 138808 Kbytes > Dbspaces > address number flags fchunk nchunks flags owner name > c036100 1 1 1 1 N > informix rootdbs > c036978 2 1 2 1 N > informix inflogs > Chunks > address chk/dbs offset size free bpages flags pathname > c036170 1 1 0 50000 48913 > PO- /dev/vx/rdsk/datadg/rootspac > c0362b8 2 2 0 1005109 947056 PO- > /dev/vx/rdsk/datadg/vol02 > > Regards > > David M MacAllister > Securicor Omega International

A Long transaction occurs primarily because of shortage of log space. It is theoretically possible to calculate the maximum amount of log space one needs and configure the size of the logical log accordingly. But, considering the amount of free space you have in relation to the total space within your instance, I would just blindly add space. How much? Well, I'd treble to quadruple it, putting them into inflogs. Rudy BTW, going by the number and size of existing logs and your onstat -d output, it does appear as if your current logs are in inflogs rather than rootdbs. In article <7u7lnf$jdm$1@news.xmission.com>, david.mcallister@soi.co.uk wrote: > > > Good Evening (well it is here in Scotland), > > I have a query regarding the size and number of logical logs. Until > lately, we had around 80 users logging into our informix database and > running various reports, updates etc. Unfortunately (?) we no longer have > the same amount of users but we still require to maintain the database, and > indeed, we need to update the database on a nightly basis from our legacy > systems. > > For the last year or so a nightly cron job uploaded a comma delimited file > containing around 6000 entries. This however in the last month has > increased to around 20000 entries and is causing long transactions in the > upload. > > So, the question is, what should I set the size and number of logical logs > to ? > > Currently I have 24 logical logs each of size 2000. The logical logs sit > in raw disk out of the rootdb space. > > onstat -d > INFORMIX-OnLine Version 7.24.UC5 -- On-Line -- Up 3 days 01:24:05 --> 138808 Kbytes > Dbspaces > address number flags fchunk nchunks flags owner name > c036100 1 1 1 1 N > informix rootdbs > c036978 2 1 2 1 N > informix inflogs > Chunks > address chk/dbs offset size free bpages flags pathname > c036170 1 1 0 50000 48913 > PO- /dev/vx/rdsk/datadg/rootspac > c0362b8 2 2 0 1005109 947056 PO- > /dev/vx/rdsk/datadg/vol02 > > Regards > > David M MacAllister > Securicor Omega International > > Sent via Deja.com http://www.deja.com/ Before you buy.