troubleshooting Question

Proxy.pac causing slowness

Avatar of Crossroads305
Crossroads305 asked on
Web BrowsersNetworkingSoftware Firewalls
9 Comments1 Solution5207 ViewsLast Modified:
Hi, I don't know much about proxy.pac files but we seem to have an issue with ours. I'm told that the proxy.pac makes the internet unbearably slow, from what I have been told it can sometimes take 1 second to 10 for a page to load on the proxy.pac file.

I don't browse the internet much when I'm at work so I don't notice it, but I've been tasked to fix it.

From what I understand the proxy.pac is a javascript file with a series of rules, I've read up and created a few of my own which all were also too slow and certain things didn't load right.

I switch back to the old pack and it works fine, even though all the guides I look at tell me my proxy.pac file is fine, I even found a format checker which said all was good.

so I finally just took the original proxy.pac and edited it to two rules, that was still too slow, but everything worked fine. I'm not sure what else to do.

if I go directly out the proxy everything works and we don't have any page lag.
now what I'm surmising is that each individual picture load, iframe, and link gets run through the proxy.pac to see if the rule applies and that's what causes the momentary lag.

I've copied my proxy.pac below, any suggestions on how to possibly be made faster?

'function FindProxyForURL(url, host)
 if (isPlainHostName(host)|| dnsDomainIs(host, ""))
 return "DIRECT";
 else if (dnsDomainIs(host, ""))
 return "PROXY";
 return "PROXY";
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