Bug 259940

Summary: [linuxulator][wine] no way to query the maximum process ki_size
Product: Base System Reporter: Damjan Jovanovic <damjan.jov>
Component: kernAssignee: freebsd-bugs (Nobody) <bugs>
Status: In Progress ---    
Severity: Affects Some People CC: dchagin, markj, trasz
Priority: ---    
Version: 13.0-RELEASE   
Hardware: Any   
OS: Any   
Bug Depends on:    
Bug Blocks: 247219    
Attachments:
Description Flags
proposed patch none

Description Damjan Jovanovic 2021-11-20 03:17:00 UTC 
"struct kinfo_proc" lets us query the maximum RSS size ever attained using "i_rusage.ru_maxrss", but there is no similar field for the maximum "ki_size" (size of all virtual memory).

Since both Windows and Linux expect this, linuxulator's sys/compat/linprocfs/linprocfs.c function linprocfs_doprocstatus() completely omits "VmPeak", while in Wine I've had to lie that "ki_size" is both the current and maximum usage.

I wonder whether the kernel even captures that statistic?
Comment 1 Mark Johnston freebsd_committer freebsd_triage 2021-11-20 18:06:31 UTC 
Created attachment 229620 [details]
proposed patch

We don't track that value, but it is not hard to add.  See the attached patch.

One nit is that we count mappings with protection PROT_NONE, but not guard mappings, but for accounting purposes they should be treated the same.  Handling that properly would require some extra complexity that is probably not worth it.
Comment 2 Dmitry Chagin freebsd_committer freebsd_triage 2023-02-26 14:30:37 UTC 
(In reply to Mark Johnston from comment #1)
Mark, may we commit this without reporter feedback? It looks fine to me.
Comment 3 Mark Johnston freebsd_committer freebsd_triage 2023-02-27 13:36:28 UTC 
(In reply to Dmitry Chagin from comment #2)
The sys/vm portion of the patch requires some review.  I'll post it to phabricator when I get a chance.