[Pdns-dev] Patch Packet Cache be able to store multiple results for Query Cache

[bert hubert]

On Mon, Dec 24, 2007 at 02:28:36PM +0530, mital.v wrote:
>      I am sending you the patch for making the PacketCache store 
> multiple values.(inside CacheContent)
> I have used the list <string> data structure instead of string inside 
> the CacheContent class.
> Please analyze my patch and let me know if any bug is there in the 
> patch. I am also waiting for any  suggestions / improvement in my code 
> patch.
>     My code patch is for version 2.9.21.

Mr Mital,

Thank you very much for your efforts! I don't see your patch however, but
I'd love to look at it.

>     Secondly, I have found one problem in the Packet Cache. It gives me 
> packetcache miss even if I am having that content inside the cache. It 
> iterates through the whole process of going to backend and storing 
> results in packet cache again So I am getting the same value for 
> packetcache inserted again.

It only matches if all DNS flags match too - perhaps this is a problem?

>       It happens only for limited number of records out of my test to 
> 110K records. It also produces randomly means that in each newer test 
> run I am getting that packetcache miss for different records everytime.

This might be deferred lookups because of lock contention.

You can see this with the deferred-cache-lookups counter.

Thanks!

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