Date: Fri, 28 Mar 2008 20:14:58 +0300 From: Anthony Pankov <ap00@mail.ru> To: freebsd-net@freebsd.org Cc: performance@freebsd.org Subject: packet delay because of blackhole Message-ID: <1333421734.20080328201458@mail.ru>
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Just for somebody convince. While analyzing client<->server HTTPS conversation one second delay in packet exchange was discovered (strongly reproducible): Sample: N time 6 0.002303 10.28.4.14 10.28.4.50 SSL Client Hello 7 0.106710 10.28.4.50 10.28.4.14 TCP 443 > 1447 [ACK] Seq=1 Ack=103 Win=65535 Len=0 8 1.045712 10.28.4.50 10.28.4.14 TLSv1 Server Hello, Certificate, Server Hello Done Another sample: 10 0.011722 10.28.4.14 10.28.4.50 TLSv1 Application Data 11 0.115933 10.28.4.50 10.28.4.14 TCP 443 > 1442 [ACK] Seq=839 Ack=519 Win=65466 Len=0 12 1.054037 10.28.4.50 10.28.4.14 TLSv1 Application Data The reason for delay is sysctl tcp.blackhole value grater than 0, much to surprise. So, turning tcp.blackhole to 0 eliminate any delay (strongly reproducible). System: FreeBSD 6_2_stable -- Best regards, Anthony mailto:ap00@mail.ru
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