Add A section on the retransmit timer sysctls.

MFC after:	3 days
This commit is contained in:
Matthew Dillon 2002-08-25 01:51:57 +00:00
parent 760e2cb04a
commit 667137d174

View File

@ -300,6 +300,19 @@ no reseeding will occur.
Reseeding should not be necessary, and will break
.Dv TIME_WAIT
recycling for a few minutes.
.It tcp.inet.tcp.rexmit_{min,slop}
Adjust the retransmit timer calculation for TCP. The slop is
typically added to the raw calculation to take into account
occassional variances that the SRTT (smoothed round trip time)
is unable to accomodate, while the minimum specifies an
absolute minimum. While a number of TCP RFCs suggest a 1
second minimum these RFCs tend to focus on streaming behavior
and fail to deal with the fact that a 1 second minimum has severe
detrimental effects over lossy interactive connections, such
as a 802.11b wireless link, and over very fast but lossy
connections for those cases not covered by the fast retransmit
code. For this reason we use 200ms of slop and a near-0
minimum, which gives us an effective minimum of 200ms (similar to Linux).
.It tcp.inflight_enable
Enable
.Tn TCP