Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-24 Thread Thomas Stuefe
On Mon, 21 Jun 2021 08:25:29 GMT, Volker Simonis wrote: >> Thomas Stuefe has updated the pull request incrementally with one additional >> commit since the last revision: >> >> Feedback Severin; renamed query function > > src/hotspot/os/linux/os_linux.cpp line 2142: > >> 2140: bool os::Linux

Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-24 Thread Thomas Stuefe
On Thu, 17 Jun 2021 08:53:55 GMT, Thomas Stuefe wrote: >> Proposal to add a Linux+glibc-only jcmd to manually induce malloc_trim(3) in >> the VM process. >> >> >> The glibc is somewhat notorious for retaining released C Heap memory: >> calling free(3) returns memory to the glibc, and most lib

Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-22 Thread Volker Simonis
On Thu, 17 Jun 2021 08:53:55 GMT, Thomas Stuefe wrote: >> Proposal to add a Linux+glibc-only jcmd to manually induce malloc_trim(3) in >> the VM process. >> >> >> The glibc is somewhat notorious for retaining released C Heap memory: >> calling free(3) returns memory to the glibc, and most lib

Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-21 Thread Volker Simonis
On Mon, 21 Jun 2021 12:26:20 GMT, Thomas Stuefe wrote: > _Mailing list message from [David Holmes](mailto:david.hol...@oracle.com) on > [hotspot-runtime-dev](mailto:hotspot-runtime-...@mail.openjdk.java.net):_ > > On 21/06/2021 7:58 pm, Thomas Stuefe wrote: > > > On Mon, 21 Jun 2021 09:15:05 G

Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-21 Thread Thomas Stuefe
On Thu, 17 Jun 2021 08:53:55 GMT, Thomas Stuefe wrote: >> Proposal to add a Linux+glibc-only jcmd to manually induce malloc_trim(3) in >> the VM process. >> >> >> The glibc is somewhat notorious for retaining released C Heap memory: >> calling free(3) returns memory to the glibc, and most lib

Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-21 Thread David Holmes
On 21/06/2021 7:58 pm, Thomas Stuefe wrote: On Mon, 21 Jun 2021 09:15:05 GMT, Volker Simonis wrote: I like this little new diagnostic command which I think can be quite useful in specific situations. Thanks a lot Volker! However, in contrast to other reviewers, I'd rather keep this simpl

Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-21 Thread Thomas Stuefe
On Mon, 21 Jun 2021 09:15:05 GMT, Volker Simonis wrote: > I like this little new diagnostic command which I think can be quite useful > in specific situations. > Thanks a lot Volker! > However, in contrast to other reviewers, I'd rather keep this simple and > Glibc specific instead of extend

Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-21 Thread Volker Simonis
On Thu, 17 Jun 2021 08:53:55 GMT, Thomas Stuefe wrote: >> Proposal to add a Linux+glibc-only jcmd to manually induce malloc_trim(3) in >> the VM process. >> >> >> The glibc is somewhat notorious for retaining released C Heap memory: >> calling free(3) returns memory to the glibc, and most lib

Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-21 Thread Thomas Stuefe
On Thu, 17 Jun 2021 08:53:55 GMT, Thomas Stuefe wrote: >> Proposal to add a Linux+glibc-only jcmd to manually induce malloc_trim(3) in >> the VM process. >> >> >> The glibc is somewhat notorious for retaining released C Heap memory: >> calling free(3) returns memory to the glibc, and most lib

Re: RFR: JDK-8268893: jcmd to trim the glibc heap [v2]

2021-06-17 Thread Thomas Stuefe
> The glibc is somewhat notorious for retaining released C Heap memory: calling > free(3) returns memory to the glibc, and most libc variants will return at > least a portion of it back to the Operating System, but the glibc often does > not. > > This depends on the granularity of the allocatio