varnish constant hdd write

[Alex F]

Hi,

Yesterday I compiled and installed varnish 2.1.2 instead of my old 2.0.5 
as it was randomly failing.
Now, the new varnish is constantly writing with 1-2megs to my HDD, which 
in turn causes 100% iowait, constant load of 10-20, random timeouts.
My VCL was unchanged.
The thing is that I do not know if the old varnish was constantly 
writing to my HDD, I started being aware of this problem because of the 
high load and timeouts, which I did not have until today.

Varnish has 1.6GB of virtual memory allocated, 3500 hits, and 119.000 
cached objects. I have started it using "-s 
file,/var/lib/varnish/varnish_storage.bin,2G". Is there any better 
alternative?
Also, my machine has ran out of ram, should I decrease the allocated memory?
free -m
                total        used     free    shared     buffers    cached
Mem:          3950   3891     58           0         29         2155
-/+ buffers/cache:   1706    2243
Swap:       3999       22      3977