Too many open files problem on MacOS 14.1

[daniel.daugherty at oracle.com]

On 12/13/23 4:24 AM, Andrew Haley wrote:
> On 12/13/23 06:09, Gunnar Wagenknecht wrote:
>> Greetings,
>>
>> I'm reaching out because of an issue with the JVM on MacOS that is 
>> hitting us a large scale. It started in MacOS 13 but got really worse 
>> in 14.1. We basically now need to use -XX:-MaxFDLimit on MacOS for 
>> everything with a classpath of more then 10k jars (monolith). That 
>> applies to the Java app itself as well as any Java based IDE 
>> (Eclipse, IntelliJ) or build tool.
>>
>> The reason is that the MaxFDLimit implementation on Mac is broken in 
>> the JVM. The JVM is applying a lower limit to itself. We discovered 
>> the -XX:-MaxFDLimit solution after our old workarounds of increasing 
>> the open files on MacOS stopped working.
>
> Have a look at https://bugs.openjdk.org/browse/JDK-8291060, and the 
> problem
> discussed there.
>
> Gerard Ziemski will read this, and I expect he'd like to comment.
>

This fix caused problems during testing:


     JDK-8291060 OPEN_MAX is no longer the max limit on macOS >= 10.6 
for RLIMIT_NOFILE

and was backed out using:


     JDK-8300055 [BACKOUT] OPEN_MAX is no longer the max limit on macOS 
 >= 10.6 for RLIMIT_NOFILE

I don't see the traditional [REDO] bug, but I do see this one:

     JDK-8300088 [IMPROVE] OPEN_MAX is no longer the max limit on macOS 
 >= 10.6 for RLIMIT_NOFILE

So I suspect it would be best to add comments to JDK-8300088 instead of 
JDK-8291060.

Dan