On Jan 18, 2010, at 2:16 PM, pub crawler wrote:
>> Most kernels cache recently-accessed files in RAM, and so common web servers
>> such as Apache can ?>already serve up static objects very quickly if they
>> are located in the buffer cache. (Varnish's apparent >speed is largely
>> based on the same phenomenon.) If the data is already cached in the origin
>> server's buffer >caches, then interposing an additional caching layer may
>> actually be somewhat harmful because it will add >some additional latency.
>
> So far Varnish is performing very well for us as a web server of these
> cached objects. The connection time for an item out of Varnish is
> noticeably faster than with web servers we have used - even where the
> items have been cached. We are mostly using 3rd party tools like
> webpagetest.org to look at the item times.
>
> Varnish is good as a slice in a few different place in a cluster and a
> few more when running distributed geographic clusters. Aside from
> Nginx or something highly optimized I am fairly certain Varnish
> provides faster serving of cached objects as an out of the box default
> experience. I'll eventually find some time to test it in our
> environment against web servers we use.
I have a hard time believing that any difference in the total response time of
a cached static object between Varnish and a general-purpose webserver will be
statistically significant, especially considering typical Internet network
latency. If there's any difference it should be well under a millisecond.
--Michael
_______________________________________________
varnish-misc mailing list
varnish-misc@projects.linpro.no
http://projects.linpro.no/mailman/listinfo/varnish-misc
