[Spice-devel] gtk client side timeouts

[Jeremy White]

Hi,

On 3/10/17 11:01 AM, Christophe Fergeau wrote:
> On Fri, Mar 10, 2017 at 10:49:54AM -0600, Jeremy White wrote:
>> Hey all,
>>
>> We've got an issue with a remote viewer kiosk.  That is, in our normal
>> mode of operation, if something goes wrong with a client connection
>> (e.g. the sessions is killed, server restarted normally), the kiosk will
>> exit on disconnect, and we get a chance to retry the connection, or
>> present the user with a 'server down' style message.
>>
>> But in the case of a serious network problem or a server hard power
>> cycle (i.e. no TCP FIN packets can flow), our end user behavior is not
>> ideal - the kiosk appears to hang solid, requiring a power cycle.
>>
>> That's because we've got the stock keepalive timeouts, or about 2 hours
>> and 11 minutes, before the client sees the disconnect.
>>
>> Now this is a relatively rare occurrence, and arguably a minor nuisance,
>> but I've been asked to see what it would take to improve the situation.
>>
>> I looked for past discussions on spice-devel; I only readily found
>> discussion of the keepalive parameters on the server side, and it looks
>> like we take the idle timer down to 10 minutes now, from 2 hours.  I
>> didn't find discussion of something similar client side.
>>
>> Have we considered tuning them on the spice-gtk client side?
>>
>> The attached patch applies a roughly 75 second timeout for me; is this
>> something that would be viable to add to the gtk client, even if only as
>> an option?
> 
> Ah, I've coincidentally been looking at this this week too, not with the
> same goal in mind though, my problem is SPICE connection sometimes
> getting dropped if idle for too long. But the current answer is also
> tweaking TCP keepalives.
> Definitely no objection having some form of keepalive client sides,
> though your proposed change is not going to work for the Windows client.
> 
> I've made some good progress on patches to add both Windows/linux
> support to glib, but need to finish them up ;)

Ping?  This problem persists, and the patch I sent then:
 
https://lists.freedesktop.org/archives/spice-devel/attachments/20170310/6938c6dc/attachment.diff

has been working for us for a number of years without any unexpected 
consequences.

Could I submit this patch and we remove it when there is a better 
solution that also supports Windows?

Cheers,

Jeremy