Question

I am getting this error message when starting my local neo4j server for development (live I am using the heroku neo4j addon).

WARNING: Detected a limit of 2560 for maximum open files, while a minimum value of 40000 is recommended.

WARNING: Problems with the operation of the server may occur. Please refer to the Neo4j manual regarding lifting this limitation.

I have googled, tried to search the manual on site, downloaded and searched the pdf. (To hopefully eliminate the RTFM responses). I cannot find how to do this in Mac OSX 10.6. Sounds like something pretty basic that it’s just assumed I’ll know. Any thoughts?

Answer 1

The best way to change this would be to set the resource limits in a launchd.plist format and use that to spawn your development shell or your database process. Once you have your launchd job, you can load, unload and have the system start it up and respawn it as needed.

See man launchd.plist – look for:

 HardResourceLimits <dictionary of integers>
 Resource limits to be imposed on the job. These adjust variables set with setrlimit(2).  The follow-
 ing keys apply:

       NumberOfFiles <integer>
       The maximum number of open files for this process.  Setting this value in a system wide daemon
       will set the sysctl(3) kern.maxfiles (SoftResourceLimits) or kern.maxfilesperproc
       (HardResourceLimits) value in addition to the setrlimit(2) values.

I’ve also had good luck with the published guides and blogs for Oracle 10g installs as they explain fairly well what sysctl and kernel values Oracle likes to change on Snow Leopard (and other releases) since Lion is a bit more launchd centric than past releases and you indicated a 10.6 for your base OS.