Long delays and Error 503's from Varnish

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zoon_unit's picture

I've got a Mercury 1.2 site set up on Linode and just installed a new site. In some page loads I get extremely long delays. (30 seconds or more) On other page loads, they come up almost instantly. I know the Varnish 503 error is probably because it is waiting for Apache to respond. The question becomes, why is Apache so slow??

What is the best method or analysis package for tracking down these extreme slowdowns???

thanks