diff options
| author | Olivier Brunel <jjk@jjacky.com> | 2016-08-16 20:32:02 +0200 |
|---|---|---|
| committer | Daniel Stenberg <daniel@haxx.se> | 2016-09-04 13:11:23 +0200 |
| commit | 4b86113f5ed66270364738a351ebb5bb23cd0882 (patch) | |
| tree | 46e47059805dc88774d9a29e5210c6496e031c37 /docs/libcurl | |
| parent | 85e5ebe75f8432333a53832d7acd0ebd65ae2506 (diff) | |
speed caps: not based on average speeds anymore
Speed limits (from CURLOPT_MAX_RECV_SPEED_LARGE &
CURLOPT_MAX_SEND_SPEED_LARGE) were applied simply by comparing limits
with the cumulative average speed of the entire transfer; While this
might work at times with good/constant connections, in other cases it
can result to the limits simply being "ignored" for more than "short
bursts" (as told in man page).
Consider a download that goes on much slower than the limit for some
time (because bandwidth is used elsewhere, server is slow, whatever the
reason), then once things get better, curl would simply ignore the limit
up until the average speed (since the beginning of the transfer) reached
the limit. This could prove the limit useless to effectively avoid
using the entire bandwidth (at least for quite some time).
So instead, we now use a "moving starting point" as reference, and every
time at least as much as the limit as been transferred, we can reset
this starting point to the current position. This gets a good limiting
effect that applies to the "current speed" with instant reactivity (in
case of sudden speed burst).
Closes #971
Diffstat (limited to 'docs/libcurl')
| -rw-r--r-- | docs/libcurl/opts/CURLOPT_MAX_RECV_SPEED_LARGE.3 | 5 | ||||
| -rw-r--r-- | docs/libcurl/opts/CURLOPT_MAX_SEND_SPEED_LARGE.3 | 6 |
2 files changed, 5 insertions, 6 deletions
diff --git a/docs/libcurl/opts/CURLOPT_MAX_RECV_SPEED_LARGE.3 b/docs/libcurl/opts/CURLOPT_MAX_RECV_SPEED_LARGE.3 index 031f2cd39..c99ff61e3 100644 --- a/docs/libcurl/opts/CURLOPT_MAX_RECV_SPEED_LARGE.3 +++ b/docs/libcurl/opts/CURLOPT_MAX_RECV_SPEED_LARGE.3 @@ -31,9 +31,8 @@ CURLcode curl_easy_setopt(CURL *handle, CURLOPT_MAX_RECV_SPEED_LARGE, curl_off_t speed); .SH DESCRIPTION Pass a curl_off_t as parameter. If a download exceeds this \fIspeed\fP -(counted in bytes per second) on cumulative average during the transfer, the -transfer will pause to keep the average rate less than or equal to the -parameter value. Defaults to unlimited speed. +(counted in bytes per second) the transfer will pause to keep the speed less +than or equal to the parameter value. Defaults to unlimited speed. This option doesn't affect transfer speeds done with FILE:// URLs. .SH DEFAULT diff --git a/docs/libcurl/opts/CURLOPT_MAX_SEND_SPEED_LARGE.3 b/docs/libcurl/opts/CURLOPT_MAX_SEND_SPEED_LARGE.3 index c2c6336f1..7f3efe57c 100644 --- a/docs/libcurl/opts/CURLOPT_MAX_SEND_SPEED_LARGE.3 +++ b/docs/libcurl/opts/CURLOPT_MAX_SEND_SPEED_LARGE.3 @@ -31,9 +31,9 @@ CURLcode curl_easy_setopt(CURL *handle, CURLOPT_MAX_SEND_SPEED_LARGE, curl_off_t maxspeed); .SH DESCRIPTION Pass a curl_off_t as parameter with the \fImaxspeed\fP. If an upload exceeds -this speed (counted in bytes per second) on cumulative average during the -transfer, the transfer will pause to keep the average rate less than or equal -to the parameter value. Defaults to unlimited speed. +this speed (counted in bytes per second) the transfer will pause to keep the +speed less than or equal to the parameter value. Defaults to unlimited +speed. This option doesn't affect transfer speeds done with FILE:// URLs. .SH DEFAULT |