On 2014-08-21, Federico Giannici <[email protected]> wrote: > On 08/21/14 19:03, Stuart Henderson wrote: >> On 2014-08-21, Federico Giannici <[email protected]> wrote: >>> We are using a firewall/qos server with a lot of HFSC queues. >>> We have just switched to the new queueing system of 5.5. >>> We'd like to get rid of custom kernels because now there is no longer >>> the limit of 64 HFSC classes, but I have recently read that there are >>> still limits to the efficacy of the queueing system with the standard >>> 100 HZ in systems with high speed connections. >>> >>> Is this still true? >>> If so, is there some way to calculate, or at least have an idea, of the >>> minimum HZ value required for a given output speed and queues parameters? >>> >>> Thanks. >>> >>> >> >> Queues with the default HZ are OK with high speed connections. The problem >> is with *low* speed connections. I don't know how to calculate values though. > > We have many slow speed queues (most of them from 2Mbps to 12Mbps and a > few with higher speeds) with a relatively high speed output interface > (currently 500Mbps).
500Mbps still sounds like a queue, since interfaces are 10Mb, 100Mb, 1Gb, 10Gb ... > Any idea of HZ required in this situation? I don't - experimentation is probably required.
