Subject: Re: Very slow pipe/TCP connection in 1.6_BETA4
To: <>
From: David Laight <>
List: current-users
Date: 07/12/2002 21:13:24
> There are two tests that are illustrative. In both, the tester sends a NOP
> PDU (48 bytes) with 4k of attached data. In one case, the target only
> sends a reply (48 bytes). In the other, it sends a reply and a copy of the
> 4k of data. The first test flies along at line speed. The second one gets
> hit by the .2 second delay.

Stinks of a single bit heuristic being used to determine whether
to wait for more data.  The short write gets sent immediately
because the previous block was sent on timeout, and the long block
gets sat on because it should (or could) have been usefully
attached to the previous block.

OTOH I haven't looked at the code, OTOTOH I have written 'ack'
strategies for comms stack in the past....


David Laight: