Re: running out of file descriptors

[Erik Fair <fair%netbsd.org@localhost>]

We (NetBSD) still have a historical construct in config(5) that a bunch of system-wide limits like MAXFILES are calculated from a presumed average or median amount of those resources per user, expressed as multiples of “maxusers [n]” in config(5).

We may wish to survey typical applications now in use and see what the distribution of {file, socket} descriptors “per user” looks like (standard distribution? bi-modal? tri-modal?) and see if our current multipliers still reflect actual use. Or perhaps use a different scheme/model for sizing kernel & system resource limits than “n per user."

I’ve had to contend with our assumed limits by significantly raising the per-process soft limits for programs like pkgsrc/www/privoxy wherein descriptor use is proportional to traffic/clients rather than to number of processes.

	something to consider,

	Erik Fair

> On Apr 18, 2018, at 02:27, Thomas Klausner <tk%giga.or.at@localhost> wrote:
> 
> On Wed, Apr 18, 2018 at 11:10:37AM +0200, Martin Husemann wrote:
>> On Wed, Apr 18, 2018 at 11:08:49AM +0200, Thomas Klausner wrote:
>>> Did anyone else notice something similar?
>> 
>> Check with fstat(1) ?
> 
> Good idea. Right now, the top ones seem nearly ok:
> 
> # fstat | sed "s/ [0-9].*$//" | sort | uniq -c | sort -n
> ...
>  24 root     pbulk-build
>  26 wiz      at-spi2-registry 
>  30 wiz      at-spi-bus-launc
>  34 wiz      zsh       
>  40 wiz      dbus-daemon
>  42 root     sh        
>  45 root     X          
>  49 bulk     sh        
>  56 bulk     cc1plus   
>  62 root     sshd       
>  73 wiz      transmission-gtk
>  92 root     master      
> 115 wiz      syncthing  
> 142 wiz      firefox   
> 
> I wonder about some of the numbers (master 92, sshd 62) but I don't
> see anything eating thousands. Perhaps it's one particular package.
> Thomas