Server response time discrepancy.

Dear All,

We are maintaining a site. All the server infrastructure is physically located in Singapore (including the HAProxy load balancer).

We have experienced situations where people from USA had errors accessing the site but here from Singapore the site worked fine.

We have been diving into HAProxy logs for a few days and discovered that the "Tr" values (aka server response time) when the site is being accessed from Singapore are about 10ms (or less) but when accessed from US is more than 40000ms. The difference is huge.

A few log lines that illustrate this (please pay attention into the FOURTH digit):

1. Accesses from Singapore (Timing Events).- 4/0/2/9/311 (Tr = 9) 4/0/2/9/165 (Tr = 9) 12/0/2/2/20338 (Tr = 2) 8/0/1/2/364829 (Tr = 2) 8/0/2/2/390360 (Tr = 2)
   ---
   
2. Accesses from USA (Timing Events).- 3/0/2/43286/43409 (Tr = 43286) 3/0/3/56757/56883 (Tr = 56757) 4/0/1/40364/40580 (Tr = 40364) 3/0/4/102493/102616 (Tr = 102493) 4/0/3/125353/125487 (Tr = 125353)
   ---
   

Do you think that there is something wrong with the network or the application? Are this values common (i.e. too high, too low...)?

Thank you so much,
unai Received on 2008/06/19 11:06