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.
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]"
}