-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Brooke,
On 5/31/12 11:51 AM, Hedrick, Brooke - 43 wrote: > Our release cycle has us releasing many applications on many JVMs > every week. From time to time, these applications have issues in > them where someone has made a code change that requires 2 > connections per request instead of 1. In those cases, we > temporarily increase the MaxActive to accommodate the issue > introduced. We do this by using JMX as well as updating the > server.xml ( in case the JVM is restarted for some reason ). In > some cases an application is released that shares a datasource with > another application and the MaxActive isn't large enough to > accommodate both apps. By using JMX, we are able to increase > MaxActive without having to take the JVM down to resolve this. > > We also have cases where applications are released with connection > pool leaks. When this happens, we catch problems because we keep > the pools only big enough to service demand. We will see > connection pools hit 100% usage and thread pools increase rapidly > due to waiting on connections. We do this to prevent the database > from being hit overly hard by a single application. We also do not > use the removeAbandoned settings today in favor of failing fast. > This way the App Server suffers not the DB. Our Tomcat hosts and > JVMs greatly outnumber our DB hosts. Gotcha. > What do you do today to reset or resize connection pools? We simply use maxActive with log/removeAbandoned. Fortunately, we have a very well-behaved application that neither leaks connections nor requires two connections at once, so we don't have any deadlocks. We run with maxActive=20 and that services our current load requirements with no problems (and no 'abandoned' notifications occur unless some query takes a very long time to execute -- which does happen every few months). We never have to recycle our entire pool for any reason. - -chris -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.17 (Darwin) Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk/HxX0ACgkQ9CaO5/Lv0PCY+wCdF0++ISNqpl6e2gx4Jp8xXAoI l5QAn1RvRkYlpbXstny7EaChtZI0yqT0 =CCxl -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
