[CRIU] [PATCH] early_init: Force to unlimit files on early init

[Cyrill Gorcunov]

On Tue, Mar 12, 2019 at 10:51:32PM +0200, Mike Rapoport wrote:
> On Tue, Mar 12, 2019 at 11:43:02PM +0300, Cyrill Gorcunov wrote:
> > On Tue, Mar 12, 2019 at 10:35:17PM +0200, Mike Rapoport wrote:
> > > On Tue, Mar 12, 2019 at 08:29:25PM +0300, Cyrill Gorcunov wrote:
> > > > From: Cyrill Gorcunov <gorcunov at virtuozzo.com>
> > > > 
> > > > It is so because when we checkpoint containers with huge number
> > > > of files opened we get
> > > > 
> > > >  | (00.659733) Error (criu/util.c:403): Can't open 57950: Too many open files
> > > >  | (00.659741) Error (criu/proc_parse.c:2399): Can't open 57950/task on procfs: Too many open files
> > > >  | (00.675635) Error (criu/cr-dump.c:2111): Dumping FAILED.
> > > >  | Failed to checkpoint the Container
> > > > 
> > > > simply because we're opening more files for criu itself. This mostly
> > > > reverts a148e87469a36dc75e263259e39ed30336343fc8
> > > > 
> > > > Signed-off-by: Cyrill Gorcunov <gorcunov at virtuozzo.com>
> > > > ---
> > > >  criu/cr-restore.c | 32 --------------------------------
> > > >  criu/crtools.c    | 33 +++++++++++++++++++++++++++++++++
> > > >  2 files changed, 33 insertions(+), 32 deletions(-)
> > > 
> > > ...
> > >  
> > > > diff --git a/criu/crtools.c b/criu/crtools.c
> > > > index 3f64000c1e87..5da09beaa75f 100644
> > > > --- a/criu/crtools.c
> > > > +++ b/criu/crtools.c
> > > > @@ -51,8 +51,41 @@
> > > >  #include "sysctl.h"
> > > >  #include "img-remote.h"
> > > >  
> > > > +static void rlimit_unlimit_nofile_self(void)
> > > 
> > > Nit: does '_self' suffix have some real meaning? Can we just drop it?
> > > Same for the pr_{perror,debug}
> > 
> > It means that we're unlimiting _own_ resources not
> > some other pid.
> 
> Well, for me the '_self' was excessive and it was clear enough that a
> static function called from the early_init() would limit own resources.

You know, I'm fine with _self dropped (thought I personally prefer
it to have) but I have no strong objectives. So ok, will drop.

> > > > +	if (prlimit(getpid(), RLIMIT_NOFILE, &new, NULL)) {
> > > > +		pr_perror("rlimir: Can't setup RLIMIT_NOFILE for self");
> > > 
> > >                           ^ rlimit
> > > 
> > 
> > ? Unfortunately our logger doesn't allow to setup temp prefixes,
> > so I put rlimit here for easier greps.
> 
> There's a typo: rlimi*r* ;-)

Ah, indeed, sorry :)