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I was monitoring the packets communication between my client server and sql server. There is query which retrieves about 10mb of data. during which there are a lot of windows update. Also while transferring the data from sql server in half way of transfer would be TCP ACK from the client and then after 25ms there would be window update after which only the transfer would start again. This pattern would continue till the end of transfer.
Questions is 1) Is this a normal behavior while transferring large data. 2) during this transfer there where 2 window zero request also. Is having 2 window zero request for this transaction acceptable or could it be interpreted that the client machine was not able sufficient powerful enough to process this?

asked 06 Jul '14, 01:44

scara's gravatar image

accept rate: 0%

Zero window is not a request. It is the client machine announcing that it has no more room in its receive buffer, which forces the sender to stop transmitting. This means that the client application is not reading the data as fast is it's coming in.

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answered 06 Jul '14, 14:57

Jim%20Aragon's gravatar image

Jim Aragon
accept rate: 24%

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question asked: 06 Jul '14, 01:44

question was seen: 1,340 times

last updated: 06 Jul '14, 14:57

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