samba - Feb 2019 - Question about Sizing of Samba Linux Server

Hello all,

I'm jumping into this mailing list because my question still unsolved after
Googling the web.

Do you know any performance of sizing recommendations about Samba 4.7.1 ?

For few informations :

2vCPUs / 1 Core
8Go of RAM
140 simultaneous Windows users / 250 at most
20 NFS shares mounted via fstab


This question because my RAM is all eated up in the buffer/cache (normal
according to last chapter of :
https://wiki.samba.org/index.php/Performance_Tuning).

Users are not complaining but I don't know if the servers is needing more
or less.

Any advice will be greatly appreciated, thanks.

*Geoffrey MEZERETTE* • Ingénieur Systèmes et Réseaux • Enovea •
16, rue Jacques Monod • 76130 Mont Saint Aignan • Standard +33 (0) 2 32 18
82 66 • geoffrey.mezerette at enovea.net •
www.enovea.net <http://www.enovea.net/>• <http://www.enovea.net/>

Memory taken up by the buffer cache is available for use.  On a Linux
system writes to disk occur asynchronously, th e process first moves the
data into system buffers, then continues with what it was doing.  At a
later time the operating system moves the data from memory to disk, but
does not immediately blank the page.  Pages which are left as a copy of
disk are therefore a cache, but can be released if another process
requires them.  Indeed, they are _only_ released when required, so that
over time all memory pages end up being used, or dwelling in the buffer
cache.  Cached pages are recovered very quickly with a soft page fault,
going to disk requires a hard page fault which is dealt with a disk speeds.

Be aware that the foregoing only applies to single node machines
(including those servering the network via NFS of Samba).  In a true
cluster environment with a SAN, the on-disk version may be updated by
another node, so the cluster-wide filesystem needs to invalidate the
cache, but that is a whole new level of complexity.

The short answer therefore is that "my RAM is all eated up in the
buffer/cache" is indeed normal.  In general, more RAM is nearly always
better, but if "users are not complaining" you may have difficulty
getting past management!

HTH,

Martin

On 05/02/2019 13:20, Geoffrey MEZERETTE via samba wrote:
> Hello all,
>
> I'm jumping into this mailing list because my question still unsolved
after
> Googling the web.
>
> Do you know any performance of sizing recommendations about Samba 4.7.1 ?
>
> For few informations :
>
> 2vCPUs / 1 Core
> 8Go of RAM
> 140 simultaneous Windows users / 250 at most
> 20 NFS shares mounted via fstab
>
>
> This question because my RAM is all eated up in the buffer/cache (normal
> according to last chapter of :
> https://wiki.samba.org/index.php/Performance_Tuning).
>
> Users are not complaining but I don't know if the servers is needing
more
> or less.
>
> Any advice will be greatly appreciated, thanks.
>
> *Geoffrey MEZERETTE* • Ingénieur Systèmes et Réseaux • Enovea •
> 16, rue Jacques Monod • 76130 Mont Saint Aignan • Standard +33 (0) 2 32 18
> 82 66 • geoffrey.mezerette at enovea.net •
> www.enovea.net <http://www.enovea.net/>•
<http://www.enovea.net/>