On 17-04-18 06:12 PM, Jakub Kicinski wrote:
Noob question - would it be an option to establish some form of streaming statistic updates out of the kernel?
It would be more efficient, certainly. Current polling approach is not as bad though (you send one extra kernel message) and is more reliable (events generated by the kernel are not reliably delivered to user space).
The notion of user space trying to keep track of the time here seems a bit shaky.
You mean the patch i sent or suggestion you are making would be more shaky? I see both being fine from that perspective - you dont need 100% accuracy. Just something that is within reason of a small delta of time.
Would it be an option with netlink to open a socket and request specific set of statistic to be dumped on it periodically if they changed? I guess it would be way more code that the patch you present...
Sensible but like you said more code. For efficiency you will need to have some tweakables. Possibly something that could specify "send me X events or whatever youve accumulated in Y seconds" etc. Note: Here we open one socket; and every X seconds we ask the kernel to give us whatever changed in the last X seconds or so. There are some drawbacks. If it takes you longer than X seconds to walk over everything then you are in trouble. The earlier patch speeds us up a bit. And I have some other rough patches I am where we could have multiple threads asking for both time and specific index ranges to make sure we got everything in time. For a couple of million actions, I havent found big need for those yet;-> cheers, jamal
