Varnish use for purely binary files

Michael S. Fischer michael at dynamine.net
Tue Jan 19 01:39:48 CET 2010


On Jan 18, 2010, at 4:15 PM, Ken Brownfield wrote:

> Ironically and IMHO, one of the barriers to Varnish scalability is its thread model, though this problem strikes in the thousands of connections.

Agreed.  In an early thread on varnish-misc in February 2008 I concluded that reducing thread_pool_max to well below the default value (to 16 threads/CPU) was instrumental in attaining maximum performance on high-hit-ratio workloads.   (This was with Varnish 1.1; things may have changed since then but the theory remains.)

Funny how there's always a tradeoff:

Overcommit ->  page-thrashing death
Undercommit -> context-switch death

:)

--Michael


More information about the varnish-misc mailing list