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jinzhaoyu / speedtracer

Automatically exported from code.google.com/p/speedtracer
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WebKit delivering Timeline resource messages with negative time. #29

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago 
Something changed recently in WebKit and we are now receiving records with 
negative time values. This needs to be investigated.

Original issue reported on code.google.com by knor...@google.com on 30 Aug 2010 at 6:40

GoogleCodeExporter commented 9 years ago 
I have observed negative values being reported for "Response Timing". My 
suspicion is that NETWORK_RESOURCE_FINISH is being triggered prematurely.  The 
negative value I see for Response Timing seems to be equal to 
(NETWORK_RESOURCE_FINISH.time - NETWORK_RESOURCE_START.time) - 
(NETWORK_RESOURCE_RESPONSE.time - NETWORK_RESOURCE_START.time)

For example:
Request Timing  @33512ms for 906ms
Response Timing @34419ms for -861ms
Total Timing    @33512ms for 44ms

Request Timing + Response Timing = 45ms (I'm guessing rounding error).

While I don't know for sure, I would look how NETWORK_RESOURCE_FINISH is being 
triggered because my guess is that's where the problem lies.

Original comment by c.benjma...@gmail.com on 22 Dec 2010 at 9:13