From time to time on our site shows Status 500 errors because of reaching cache timeout time:

HTTP Status 500 -

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

net.sf.ehcache.constructs.blocking.LockTimeoutException: Lock timeout. Waited more than 50000ms to acquire lock for key DefaultCacheKey{uri='/envers', serverName='www.jboss.org', locale='en', params={}} on blocking cache default
net.sf.ehcache.constructs.blocking.BlockingCache.get(BlockingCache.java:532)
info.magnolia.module.cache.ehcache.EhCacheWrapper.get(EhCacheWrapper.java:74)
info.magnolia.module.cache.cachepolicy.Default.shouldCache(Default.java:96)
info.magnolia.module.cache.filter.CacheFilter.doFilter(CacheFilter.java:127)
info.magnolia.cms.filters.OncePerRequestAbstractMgnlFilter.doFilter(OncePerRequestAbstractMgnlFilter.java:60)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
info.magnolia.cms.i18n.I18nContentSupportFilter.doFilter(I18nContentSupportFilter.java:75)
info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:88)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
info.magnolia.module.cache.filter.GZipFilter.doFilter(GZipFilter.java:73)
info.magnolia.cms.filters.OncePerRequestAbstractMgnlFilter.doFilter(OncePerRequestAbstractMgnlFilter.java:60)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:84)
info.magnolia.cms.security.BaseSecurityFilter.doFilter(BaseSecurityFilter.java:64)
info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:88)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
info.magnolia.cms.security.LogoutFilter.doFilter(LogoutFilter.java:88)
info.magnolia.cms.filters.OncePerRequestAbstractMgnlFilter.doFilter(OncePerRequestAbstractMgnlFilter.java:60)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
info.magnolia.cms.security.auth.login.LoginFilter.doFilter(LoginFilter.java:77)
info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:88)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:84)
info.magnolia.cms.filters.CosMultipartRequestFilter.doFilter(CosMultipartRequestFilter.java:86)
info.magnolia.cms.filters.OncePerRequestAbstractMgnlFilter.doFilter(OncePerRequestAbstractMgnlFilter.java:60)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
info.magnolia.cms.filters.ContentTypeFilter.doFilter(ContentTypeFilter.java:102)
info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:88)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
info.magnolia.cms.filters.ContextFilter.doFilter(ContextFilter.java:120)
info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:88)
info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
info.magnolia.cms.filters.CompositeFilter.doFilter(CompositeFilter.java:66)
info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:88)
info.magnolia.cms.filters.MgnlMainFilter.doFilter(MgnlMainFilter.java:105)
info.magnolia.cms.filters.MgnlMainFilter.doFilter(MgnlMainFilter.java:216)
org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)

note The full stack trace of the root cause is available in the JBossWeb/2.0.0.GA_CP logs.
JBossWeb/2.0.0.GA_CP