[squid-users] Http write cache

[Amos Jeffries]

On 10/09/17 07:20, Olivier MARCHETTA wrote:
> Hello,
> 
> I recently set up a squid reverse proxy cache for Sharepoint Online with 
> the help of Amos.
> 
> It is now accelerating all reads by caching objects in Squid.
> 
> Now I’m facing a more tricky problem : writing objects to the parent server.
> 
> In this case it’s a direct connection and so it is slow.
> 
> I am not familiar with all the options and capabilities of the http 
> protocol, but do you know if it is possible to have an asynchronous 
> write back to the parent server to accelerate the writes ?

No, HTTP is message oriented. The equivalent of a write is a request 
message with a payload (usually PUT or POST).

Origin servers can sometimes respond to requests with payload 
("uploads") before the request has fully arrived, but any subsequent 
network issues are guaranteed to result in data loss - so the practice 
is discouraged. It is definitely not safe for a proxy to do so 
independent of the origin server.

Amos