Do you open new connection every time or do you have a pool? How often does Derby checkpoint/switch log file?
Peter ----- Original Message ----- From: Jerry Lampi <j...@sdsusa.com> To: Derby User Group <derby-user@db.apache.org> Cc: Sent: Monday, 30 September 2013, 21:28 Subject: Proper configuration for a very busy DB? We have about 30 clients that connect to our version 10.8.2.2 Derby DB. The clients are programs that gather data from the operating system of their host and then store that data in the DB, including FTP activity. Sometimes, the clients get huge flurries of data all at once and Derby is unable to handle the influx of requests; inserts, updates, etc. In addition, the clients are written so that if they are unable to talk to the DB, they queue up as much data as possible and then write it to the DB when the DB becomes available. This client queuing is a poor design, and places greater stress on the DB, as when the 30 clients finally do talk to the DB, they all dump data at once. The clients do not know about one another and therefore do not attempt any throttling or cooperation when dumping on the DB. The net effect of all this is that the DB is too slow to keep up with the clients. As clients try to feed data to the DB, it cannot accept it as fast as desired and this results in the clients queueing more data, exacerbating the issue. So the DB is very busy. The only significant thing we have done thus far is change the derby.storage.pageCacheSize=5000 and increase Java heap to 1536m. Is there a configuration considered optimal for a VERY busy Derby DB? Thanks, Jerry --- avast! Antivirus: Outbound message clean. Virus Database (VPS): 130930-0, 09/30/2013 Tested on: 9/30/2013 2:28:40 PM avast! - copyright (c) 1988-2013 AVAST Software. http://www.avast.com
