Re: [PATCH] tcp: sysctl for initial receive window
From: Jan Engelhardt <hidden>
Date: 2012-09-25 05:29:23
On Friday 2012-09-21 10:55, Jesper Dangaard Brouer wrote:
quoted hunk ↗ jump to hunk
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index c7fc107..684131c 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt@@ -257,6 +257,18 @@ tcp_frto_response - INTEGERto the values prior timeout Default: 0 (rate halving based) +tcp_init_recv_window - INTEGER + Default initial advertised receive window. Actual window size + is this value multiplied by the MSS of the connection. Its
is this value multiplied by the MSS of the connection. It is
+ possible to control/override this value per route table entry + via the iproute2 option initrwnd. + Minimum value is 1, but 2 is the recommended minimum. + The effective max value, is limited by the sockets receive
The effective max value is limited by the sockets receive
+ buffer size (default tcp_rmem[1], and possibly scaled by + tcp_adv_win_scale), and can further be limited by window
tcp_adv_win_scale) and can further be limited by window
+ clamp.
clamping.
+ Default: 10 + tcp_keepalive_time - INTEGER How often TCP sends out keepalive messages when keepalive is enabled. Default: 2hours.
The "recommended minimum" is somewhat strange from a language POV, since the recommendation is actually to _not touch_ the option at all (because the default works and there is potential abuse as Dave mentions).