I asked this question before (differently) and got some answers but now I think I understand what is really happening. I just want to confirm that I have finally understood what is happening. Given two Linux boxes running the same application, one is much slower starting (think that "slower" machine is actually a much faster box) Here are some excerpts from the catalina.out log and my guesses as to what is happening.If someone knows why this is happening for sure, I would really appreciate knowing. ----- Both Linux machines run 8.5.13 Tomcat
log here - fedora 26 running real (not virtual) Oct 25, 2017 8:38:20 AM org.apache.jasper.servlet.TldScanner scanJars INFO: At least one JAR was scanned for TLDs yet contained no TLDs. .... application @ 10/25/2017 8:38:20 Thread:15 SecurityFilter.init : log server - Ubuntu running virtual (suspect machine much faster) 25-Oct-2017 08:43:34.283 INFO [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars INFO: At least one JAR was scanned for TLDs yet contained no TLDs. ...... 25-Oct-2017 08:45:00.151 INFO [localhost-startStop-1] org.apache.catalina.util.SessionIdGeneratorBase.createSecureRandom Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [85,739] milliseconds. application @ 10/25/2017 8:45:00 Thread:15 SecurityFilter.init : Both boxes have same list for jar scan skipping - includes all application jars used (had all tomcat jars already).Note that my machine use NO time to get on with it, but 1.5 minutes is used for the server. I had an error in the scan skip lines and the time above was 10.5 minutes till I fixed it so I know CATALINA_HOME is right. (left off a comma in middle of list, so it scanned a lot of jars - :=[ ). I suspect the performance problem has nothing to do with jar scanning but has to do with the real (and virtual) server running with https not http for secure login (my development machine behind firewall with no external access) - perhaps the SecureRandom is the thing that is making this slow.
