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>> > +1 on Alan's hunch. I have not used Squid to comment on the specifics |
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>> > and also Grant stated that another proxy gave him similar symptoms. |
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>> > From my limited knowledge a proxy could be stalling because of cache |
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>> > configuration problems, like running out fs space, or inodes and also |
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>> > running out of memory if it has to process simultaneous requests from |
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>> > too many clients at a time. If the problem also manifests when the |
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>> > clients are within the same subnet, then this is unlikely to be a |
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>> > network issue. |
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>> |
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>> Which hunch was that? I snipped a lot above but I couldn't find it in |
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>> there. |
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> |
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> It was Alan's statement that this problem is not related to your AT&T router. |
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> |
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> I have to come back to this. I tried the www.google.com/nexus/ you mentioned |
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> and noticed that the page eats up 1.3MB to load fully, before it starts |
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> downloading a flash video. So seems to be a relatively large amount of data |
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> that brings up this problem and this could point to tcp window scaling. |
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|
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It also happens on very lightweight sites, but never on |
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squid-cache.org for some reason. |
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|
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>> echo 0 > /proc/sys/net/ipv4/tcp_window_scaling |
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> |
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> This is typically enabled, but if you notice that a connection stalls and then |
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> later on it works fine again, it could be related to a firewall/router not |
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> responding as it should to tcp_window_scaling. In this case disabling this |
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> would fix the problem when traversing problematic nodes. |
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> |
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> If you saw no difference, this suggests that window scaling is not an issue. |
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|
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I just tested again and 'echo 0 > |
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/proc/sys/net/ipv4/tcp_window_scaling' on both the client and server |
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did not fix the stalls. |
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> I would start with the simplest tests first, which involve isolating suspect |
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> system components one at a time. Trying to use the same laptop-desktop |
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> machines within the LAN, takes the router out the equation - full 1500 byte |
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> MTU will be used by both laptop and desktop. |
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OK I will try this as soon as I'm back in that location. |
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Thanks a lot, |
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Grant |
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