link load level that activates rule enforcement
Posted: Thu Nov 01, 2018 8:24 am
Interesting observation and question
It appears that QOS rules become enforced at some level of link load. Up until that point, bandwidth from any class seems able to exceed the set percentage at max load. That is, of course, a good thing.
QUESTION: what is the level of total link load at which max load percentages per class become enforced?
QUESTION: Is it possible to adjust that level? (officially or unofficially) without affecting max link load itself? In other words, enforce class max % assignments at a lower overall link load than max.
The reason that may be a positive feature, if at all possible, is this. In my system and in the previous one, there were plenty of times when for some unknown reason, max load decreased without introducing extra ping time. ACC did not detect it since ping time didnt change significantly. Therefore QOS didnt really do anything becasue rules were not enforced yet.
In my case this seems to only occur at levels between 50% to 90% of set max link load. Under 50% it doesnt seem necesary to worry about class assignments, and over 90% max load it seems that QOS is activated and enforcing limits. The land in between can be tricky, as it can randomly stop enforcing class % rules when under max link load but still dropping packets and a lesser important class overwhelms a higher importance class... all becasue ACC hasnt seen the need to activate rule enforcement.
yes, lowering the download total bandwidth fixes this problem, but at the cost of up to 50% bandwidth! Instead, wouldnt it be better to be able to enforce QOS rules at a lower level of link load? that would accomplish the same positive affect but allow actual max total bandwidth.
The same is true for UPLOAD bandwidth. If the level of link load which activates the rule enforcement could be adjusted lower, that would greatly improve effectiveness of upload QOS rules during these times.
Why does this happen? Why do packets get dropped without ping times being affected? My theory is a flakey link somewhere upstream within the ISP network. I suspect it is related to the use of WiFi based links in rural ISPs . these link can suffer times of low signal, and excessive dropped packets without actual link speed decreasing. This has an odd effect at the user end of appearing to be sporadic bandwidth limits without ping time increasing. This is likely due to ping times being once per second while the buffering around the flakey link causes more or less frequent bursts of packets. Overall it simply appears like total bandwidth jumps up or down in fractions of a second bursts, affecting come packets and not others. IT's a very weird thing to behold!
Sorry for the long post. I felt the need to explain as best I can to start the discussion. I love gargoyle, but it has a weakness in this area within the ACC mechanism. I think its related to the one second testing of ping times. But I do feel it could be alleviated greatly by simple adjusting the level at which ACC rules become enforced.
Thoughts?
It appears that QOS rules become enforced at some level of link load. Up until that point, bandwidth from any class seems able to exceed the set percentage at max load. That is, of course, a good thing.
QUESTION: what is the level of total link load at which max load percentages per class become enforced?
QUESTION: Is it possible to adjust that level? (officially or unofficially) without affecting max link load itself? In other words, enforce class max % assignments at a lower overall link load than max.
The reason that may be a positive feature, if at all possible, is this. In my system and in the previous one, there were plenty of times when for some unknown reason, max load decreased without introducing extra ping time. ACC did not detect it since ping time didnt change significantly. Therefore QOS didnt really do anything becasue rules were not enforced yet.
In my case this seems to only occur at levels between 50% to 90% of set max link load. Under 50% it doesnt seem necesary to worry about class assignments, and over 90% max load it seems that QOS is activated and enforcing limits. The land in between can be tricky, as it can randomly stop enforcing class % rules when under max link load but still dropping packets and a lesser important class overwhelms a higher importance class... all becasue ACC hasnt seen the need to activate rule enforcement.
yes, lowering the download total bandwidth fixes this problem, but at the cost of up to 50% bandwidth! Instead, wouldnt it be better to be able to enforce QOS rules at a lower level of link load? that would accomplish the same positive affect but allow actual max total bandwidth.
The same is true for UPLOAD bandwidth. If the level of link load which activates the rule enforcement could be adjusted lower, that would greatly improve effectiveness of upload QOS rules during these times.
Why does this happen? Why do packets get dropped without ping times being affected? My theory is a flakey link somewhere upstream within the ISP network. I suspect it is related to the use of WiFi based links in rural ISPs . these link can suffer times of low signal, and excessive dropped packets without actual link speed decreasing. This has an odd effect at the user end of appearing to be sporadic bandwidth limits without ping time increasing. This is likely due to ping times being once per second while the buffering around the flakey link causes more or less frequent bursts of packets. Overall it simply appears like total bandwidth jumps up or down in fractions of a second bursts, affecting come packets and not others. IT's a very weird thing to behold!
Sorry for the long post. I felt the need to explain as best I can to start the discussion. I love gargoyle, but it has a weakness in this area within the ACC mechanism. I think its related to the one second testing of ping times. But I do feel it could be alleviated greatly by simple adjusting the level at which ACC rules become enforced.
Thoughts?