We've been dealing with a possible performance issue over the span of a few years now. I have had multiple tickets in, each conclusion is the same, that there are no issues because ISP does an RFC test on-site and everything checks out. I now have tiers 2 and 3 looking into this, but so far they are not coming up with anything so I thought I'd try here. I apologize if this is all over the place! If any clarification is needed, or additional pcaps please let me know.
We upgraded our bandwidth at our two main offices almost a year ago from 500Mbps to 1Gbps, and we have Azure ExpressRoute 1Gbps link between these two branches. The other branch noticed a jump in performance, I noticed no difference at this branch.
Lately performance has been dragging a lot more, with no other changes having been made recently. Speed tests are showing upload speeds consistently on the lower side, at least half, if not less than half (I go off the speedtest.net app because that tends to coincide with what we should be getting for upload speeds compared to others). One thing I do find odd with the speed tests is that upload speeds will jump up to 900+, then it looks like it's throttling back down to 2-3-4-500Mbps. Based on that, I strongly feel it is an ISP issue as that they have found multiple policers on our circuits in the past, and each time they find one and remove it, I will run a speed test as soon as it is removed and speeds will be back to normal, 900+Mbps up/down. Now they are saying they are not seeing any more policers.
More to the point - I am sharing a pcap file of me uploading a 3GB file to OneDrive. I might be off on the math, but uploading a file that size over 1Gbps link should only take about 30 seconds, correct? This upload in particular took 4 minutes. Also worth noting, this was while I was directly connected to their DMARC.
As mentioned earlier, in the past when I would notice the issue and call to troubleshoot, they would 'remove the policer' and speeds would jump back up to 900+Mbps, so at this point I don't believe the issue is my laptop.
