TCP::snd_ssthresh

Description

The slow start threshold (ssthresh) is the point at which the congestion window (cwnd) grows less aggressively. When the cwnd is less than ssthresh, it roughly doubles for every cwnd worth of acknowledged data. When cwnd is greater than ssthresh, it increases by approximately one MSS for each cwnd worth of acknowledged data.
ssthresh starts at 1,073,725,440 bytes unless there is a cmetrics cache entry. When TCP detects packet loss it usually sets ssthresh to a value between 1/2 cwnd and cwnd, depending on connection conditions and the congestion control algorithm.

Syntax

TCP::snd_ssthresh

Return Value

The connection slow start threshold in bytes.

Examples

when CLIENT_ACCEPTED {
     # Get BIGIP's initial slow-start threshold.
     log local0. "BIGIP's ssthresh: [TCP::snd_ssthresh]"
 }
 when CLIENT_CLOSED {
     # Get BIGIP's last slow-start threshold.
     log local0. "BIGIP's ssthresh: [TCP::snd_ssthresh]"
 }