RFR(xs): 8251255: [linux] Add process-memory information to hs-err and VM.info

[David Holmes]

Hi Thomas,

This seems fine to me.

Thanks,
David

On 10/08/2020 9:32 pm, Thomas Stüfe wrote:
> Hi,
> 
> new version:
> 
> http://cr.openjdk.java.net/~stuefe/webrevs/8251255-add-rss-to-hs-err/webrev.01/webrev/
> 
> - changed the type of the receiver variables to ssize_t
> - enclosed mallinfo call with __GLIBC__
> 
> Thanks, Thomas
> 
> On Thu, Aug 6, 2020 at 4:01 PM Thomas Stüfe <thomas.stuefe at gmail.com 
> <mailto:thomas.stuefe at gmail.com>> wrote:
> 
>     Hi,
> 
>     may I please have reviews for this addition:
> 
>     JBS: https://bugs.openjdk.java.net/browse/JDK-8251255
>     Webrev:
>     http://cr.openjdk.java.net/~stuefe/webrevs/8251255-add-rss-to-hs-err/webrev.00/webrev/
> 
>     When analysing a customer memory leak recently I found for all
>     the information we have in the error files we miss some really
>     fundamental statistics like process virtual size and rss. Either
>     that or I am blind :)
> 
>     In case I am not blind this patch adds those statistics. I decided
>     against dumping proc files wholesale to the hs-err file, I
>     just print out what I really find useful.
> 
>     Note that among other things I print out the total size of
>     outstanding heap allocations. Note that still the best way to do
>     this is via mallinfo, and that means the returned value is int and
>     may wrap, see coding and comment. Even with this caveat though this
>     info is still very useful.
> 
>     I did a number of manual tests, the numbers seem legit.
> 
>     Looks like this:
> 
>     Process Memory:
>     Virtual Size: 7494372K (peak: 7559908K)
>     Resident Set Size: 271264K (peak: 571348K) (anon: 226460K, file:
>     44804K, shmem: 0K)
>     Swapped out: 0K
>     C-Heap outstanding allocations: 37845K
> 
> 
>     Here I simulate a C-Heap memory leak:
> 
>     Process Memory:
>     Virtual Size: 9062260K (peak: 9118772K)
>     Resident Set Size: 1941776K (peak: 1941776K) (anon: 1896872K, file:
>     44904K, shmem: 0K)
>     Swapped out: 0K
>     C-Heap outstanding allocations: 1291984K
> 
> 
>     Same leak, with the mallinfo value wrapped around:
> 
>     Process Memory:
>     Virtual Size: 12343352K (peak: 12445556K)
>     Resident Set Size: 5232084K (peak: 5281512K) (anon: 5187052K, file:
>     45032K, shmem: 0K)
>     Swapped out: 0K
>     C-Heap outstanding allocations: 15454K (may have wrapped)
> 
>     Thanks, Thomas
>