Re: bin/60443: ftp ASCII transfers are too slow

["RVP via gnats" <gnats-admin%NetBSD.org@localhost>]

The following reply was made to PR bin/60443; it has been noted by GNATS.

From: RVP <rvp%SDF.ORG@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: bin/60443: ftp ASCII transfers are too slow
Date: Tue, 14 Jul 2026 00:23:30 +0000 (UTC)

 On Mon, 13 Jul 2026, Michael van Elst via gnats wrote:
 
 > > 04:43:22.966644 IP6 ::1.65425 > ::1.65424: Flags [P.], seq 314369:328705, ack 1, win 4096, options [nop,nop,TS val 7 ecr 7], length 14336
 >
 > + 200ms
 >
 > > 04:43:23.166607 IP6 ::1.65424 > ::1.65425: Flags [.], ack 328705, win 4096, options [nop,nop,TS val 7 ecr 7], length 0
 >
 > + 0ms
 >
 > > 04:43:23.166636 IP6 ::1.65425 > ::1.65424: Flags [P.], seq 328705:342017, ack 1, win 4096, options [nop,nop,TS val 7 ecr 7], length 13312
 >
 > + 200ms
 >
 > > 04:43:23.366620 IP6 ::1.65424 > ::1.65425: Flags [.], ack 342017, win 4096, options [nop,nop,TS val 7 ecr 7], length 0
 >
 >
 > Looks more like the ACKs are delayed and less like Nagle's algorithm. No
 > idea what is happening.
 >
 
 You're right. Mebbe delayed ACK interacting badly with Nagle. Is there a 
 TCP_QUICKACK[1] knob in NetBSD?
 
 -RVP
 
 [1]: https://man7.org/linux/man-pages/man7/tcp.7.html