[TYPO3-Solr] Tomcat & Solr 4.8 / ulimit

[Lorenz Ulrich]

Hi everyone

We're using Solr on a managed dedicated server with no root priviledges 
because the hosting provider does not provide services such als Solr 4.8 
that are not available as an Ubuntu package. I adjusted the provided 
setup script to install Tomcat and Solr as a normal user and in general 
this works fine.

Now we had several crashed after Solr worked fine for some days. I could 
narrow down the problem to "Too many open files". After such a crash, 
lsof shows that Tomcat had > 4200 files open, e.g.:

java        5364   www-data 4036u      REG              252,4       101 
    5906403 
/home/www-data/solr-tomcat/solr/typo3cores/data/german/tlog/tlog.0000000000000029705

Since the ulimit for open files is set to 4096, this must be the reason 
why Tomcat crashes.

Does anyone here also host an own Solr instance? If so, do you have the 
same amount of open files, i.e. is it normal that Solr needs so many 
open files? If so, what is your ulimit setting for open files?

Thanks for your help and best regards,

Lorenz