Re: OnBar and Legato performance

Unfortunately, you didn't put what version of Informix you're using !! We have recently experienced problems with onbar with HP Omniback II using parallel archiving to a multi-loader where the engine will actually hang ! ODS 7.24.UC5 ) Apparently, each separate thread that gets spawned from the master onbar process issues a checkpoint request. If two threads issue the request at the same time, the engine will return to one but leave the other hanging. If you do an "onstat -" the server is in "CKPT BLOCKED: Archive" and all users are hung. Killing the master onbar proces using onmode -z didn't even work. We had bounce the engine and resort to doing a serial onbar archive using the -w ( whole system ) option. I guess this doesn't relate too much to your problem other than that there are many other problems with onbar that should be investigated further. Doug McAllister wrote in message <366C509C.6677EDCC@fmr.com>... >Hi all..... > >I have a performance question regarding OnBar and Legato. > >We have Legato configured to run 10 streams to each drive to 2 drives. >We are experiencing performance problems when the OnBar process starts >up to offload the log files. Near the end of the process, our system >jumps its paging rate so high that the online sessions hang and some >sessions are dropped. >Has anyone seen this symptom. > >Also, if I drop the number of Legato streams from 10 to 4, will that >have a dramatic impact on the efficiency of Legato writing to DLT >drives. I have no idea what the optimum number of streams that Legato >and DLT's should be using. > >Does anyone have insights? > >tnx..... > >Doug McAllister >Fidelity Investments >FPI&BGT Informix Support > >