Hi All, I have been perplexed by random load spikes on an 8.1.11 instance. many a times they are random, in the sense we cannot tie a particular scenario as the cause for it! But a few times we can see that when we are executing huge scripts, which include DDL as well as DML, the load on the box spikes to above 200. We see similar load spikes other times too when we are not running any such task on the DB.
During these spikes, in the 'top' sessions we see the 'idle' PG processes consuming between 2 and 5 % CPU, and since the box has 8 CPUS (2 sockets and each CPU is a quad core Intel Xeon processors) and somewhere around 200 Postgres processes, the load spikes to above 200; and it does this very sharply. We are running the scripts using psql -f, but we can see the load even while running the commands on by one! When there's no load, an strace session on an 'idle' PG process looks like: [EMAIL PROTECTED] data]$ strace -p 9375 Process 9375 attached - interrupt to quit recvfrom(9, <unfinished ...> Process 9375 detached But under these heavy load onditions, an 'idle' PG process' strace looks like: [EMAIL PROTECTED] data]$ strace -p 22994 Process 22994 attached - interrupt to quit select(0, NULL, NULL, NULL, {0, 1000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 10000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 11000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 14000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 17000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 31000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 51000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 1000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 1000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 1000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 2000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 4000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 5000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 1000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 2000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 2000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 3000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 6000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 12000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 12000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 23000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 27000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 47000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 70000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 1000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 1000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 2000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 4000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 7000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 11000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 16000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 19000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 35000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 53000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 75000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 76000}) = 0 (Timeout) select(0, NULL, NULL, NULL, {0, 102000}) = 0 (Timeout) Process 22994 detached So I guess there's something very wrong with the above 'select' calls. Can somebody please shed some light on this? Let me know what OS/hardware specs you need. Any help is greatly appreciated. Thanks in advance, -- [EMAIL PROTECTED] [EMAIL PROTECTED] gmail | hotmail | indiatimes | yahoo }.com EnterpriseDB http://www.enterprisedb.com Mail sent from my BlackLaptop device