Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!sun-barr!oliveb!amdahl!dgcad!gary From: gary@dgcad.SV.DG.COM (Gary Bridgewater) Newsgroups: news.software.b Subject: dbz caveat Keywords: dbz runtime Message-ID: <1139@svx.SV.DG.COM> Date: 26 Sep 89 07:56:41 GMT Reply-To: gary@svx.SV.DG.COM (Gary Bridgewater) Organization: Data General SDD, Sunnyvale, CA Lines: 22 I switched to dbz in my B 2.11.17 and have noticed a pretty good performance improvement for several weeks now. Suddenly, last Thursday my expire times jumped from an hour or so to 4+ hours (I keep a 30 day history). Then, starting Friday, I noticed that processing incoming news was taking between 2 and 3 minutes per article whether it was a duplicate or not. I spent the whole weekend fiddling and getting farther and farther behind - 2 minutes to process an article means you only get to process 720 articles a day. Finally, tonight, I decided I better rethink DBZ so I went into the code and found /* Set this to the something several times larger than the maximum # of lines in a history file. It should be a prime number. */ #define INDEX_SIZE 99991L My history file is sitting at 5Mb, an average history line is ~40 bytes -> 120,000 lines. OOOPS! I bumped INDEX_SIZE up to 1000003, did an expire -R ( 30 minutes ), and am now processing articles at a rate of 4-5/minute. Another symptom of this is if your server nntpd's start chewing up cpu time. -- Gary Bridgewater, Data General Corp., Sunnyvale Ca. gary@sv4.ceo.sv.dg.com or {amdahl,aeras,amdcad,mas1,matra3}!dgcad.SV.DG.COM!gary No good deed goes unpunished.