Hello all, thanks a lot for your help so far. You all where right about the IDE drive is somehow caching the data. See the test results below. I also get different tps values every time I run pgbench on PC1 (between 300 and 80 tps for 100 transactions).
I don't think it's a good idea to disable fsync even if ext3 (doing a sync also every x second or so) and a UPS is used. Christian PC1 (IDE): ---------- fsynch on: ---------- number of transactions per client: 100 number of transactions actually processed: 100/100 tps = 213.115558 (including connections establishing) tps = 214.710227 (excluding connections establishing) number of transactions per client: 10000 number of transactions actually processed: 10000/10000 tps = 126.159130 (including connections establishing) tps = 126.163172 (excluding connections establishing) fsynch off: ----------- number of transactions per client: 100 number of transactions actually processed: 100/100 tps = 413.849044 (including connections establishing) tps = 419.028942 (excluding connections establishing) number of transactions per client: 10000 number of transactions actually processed: 10000/10000 tps = 166.057838 (including connections establishing) tps = 166.064227 (excluding connections establishing) PC2 (SCSI): ----------- fsynch on: ---------- number of transactions per client: 100 number of transactions actually processed: 100/100 tps = 44.640785 (including connections establishing) tps = 44.684649 (excluding connections establishing) number of transactions per client: 10000 number of transactions actually processed: 10000/10000 tps = 42.322486 (including connections establishing) tps = 42.324096 (excluding connections establishing) fsynch off: ----------- number of transactions per client: 100 number of transactions actually processed: 100/100 tps = 910.406861 (including connections establishing) tps = 925.428936 (excluding connections establishing) number of transactions per client: 10000 number of transactions actually processed: 10000/10000 tps = 957.376543 (including connections establishing) tps = 957.603815 (excluding connections establishing) ****************************************** The information contained in, or attached to, this e-mail, may contain confidential information and is intended solely for the use of the individual or entity to whom they are addressed and may be subject to legal privilege. If you have received this e-mail in error you should notify the sender immediately by reply e-mail, delete the message from your system and notify your system manager. Please do not copy it for any purpose, or disclose its contents to any other person. The views or opinions presented in this e-mail are solely those of the author and do not necessarily represent those of the company. The recipient should check this e-mail and any attachments for the presence of viruses. The company accepts no liability for any damage caused, directly or indirectly, by any virus transmitted in this email. ****************************************** ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
