Hmmmm....
I just redid my tests with:
BalancerMember ajp://localhost:8010 min=15 max=*50* smax=30 ttl=900
keepalive=Off timeout=900
and
<Connector port="8010"
minSpareThreads="15" maxSpareThreads="30"
maxThreads="*51*" acceptCount="*0*"
tomcatAuthentication="false"
useBodyEncodingForURI="true" URIEncoding="UTF-8"
enableLookups="false" redirectPort="8443"
protocol="AJP/1.3" />
and
ab -n 100 -c *50* http://jessh03l.ptcnet.ptc.com/TestApp/test.jsp?secs=3
I (after about 3 seconds) get
SEVERE: All threads (51) are currently busy, waiting. Increase
maxThreads (51) or check the servlet status
and I eventually get exactly 1 lost request. I'm baffled as to why this
can occur.
Something's still doesn't seem quite right here.
What's even weirder is that I only get this issue with the first ab run
after restarting Tomcat. If I do the same test again (any number of
times) I don't lose any requests.
I can get the same result by restarting and doing 2 ab runs with "-n
100" in fairly short secession, so this isn't some ab error. By "fairly
short", I don't mean very short -- I left a good 5 seconds between runs.
I find that using a max of 49 in Apache seems to work reliably, but I'm
struggling to understand: (1) why I have to have 2 more Tomcat connector
threads allowed than the number of connections I can possibly have and
(2) whether "2" is always the safe buffer or whether I'll need 9 on an 8
CPU box or some such.
--
Jess Holle
