Re: [squid-users] Re: Squid Cache flush

Are you sure that you need to do this?
Squid should be able to tell the difference between static and dynamic
content.

We have a dynamic JSR-168/268 portal based on Tomcat and Jetspeed
sitting behind Apache and Squid and we have never had to intervene with
Squid for 3 years.
We also have lots of Wordpress CMS sites.

The user gets the latest information on every page load regardless of
the URL being the same.

What exactly would cause you to trigger a flush of the cache?

Ron

On 21/04/2011 11:30 AM, Jawahar Balakrishnan (JB) wrote:
> I would rather not do a restart of anything unless absolutely required
>
> Here are the challenges we face
>
> 1) We are trying to deploy Suqid as a reverse-proxy in front of a CMS
> 2) We want to trying find a balance between keeping the content fresh
> without affecting performance by frequently expiring content.
>
> Our current reverse proxy solution allow us to flush the entire cache
> without having to restart but in limited testing Squid seemed to
> perform much better and we would prefer to use Squid but still retain
> the functionality of being able to flush the entire cache periodically
> via cron or when in case of an emergency.
>
> Cache-control headers are fine and will work in case of limited number
> of objects.
>
> Thanks
> JB
>
>
> On Tue, Apr 19, 2011 at 7:27 PM, Amos Jeffries<squid3_at_treenet.co.nz> wrote:
>> On Tue, 19 Apr 2011 11:14:55 -0400, Jawahar Balakrishnan (JB) wrote:
>>> I am looking to deploy Squid as a reverse proxy and i had couple of
>>> questions. We currrently use Bluecoat and Sun Web proxy and i am able
>>> to do the following things
>>>
>>> 1) How would i flush objects from cache?
>> The whole lot:
>> http://wiki.squid-cache.org/SquidFaq/ClearingTheCache
>>
>> or individually via:
>> HTTP "PURGE" requests
>> HTCP "CLR" requests
>>
>> squidpurge tool commands.
>>
>>
>>> 2) Can i flush the entire cache without restarting Squid?
>> Yes ... but it takes a LONG time to do N objects individually.
>> Restart without a cache to load takes milliseconds.
>>
>>> 3) Can i set the configuration to expire objects at a certain time
>>> every day regardless of when the object was cache during the previous
>>> 24 hours?
>> Use of the Expiry and Cache-Control mechanisms properly can do just about
>> anything. Correct use will make all proxies not just your reverse one handle
>> the site fine and remove a lot of customer problems.
>>
>> Objects which arrive with header "Expires: XX" will expire at XX timestamp
>> and be replaced on their next use.
>>
>>
>>
>> Amos
>>
>>
Received on Thu Apr 21 2011 - 16:10:36 MDT