Hi Ram, That sounds like a great idea. Let's try to generalize the idea and see how to attack it. It looks like we need counters/statistics per verbs object. I noticed that you require specific measurements the objects. However - I see several potential issues here: First - if you manage to find a vendor to add those counters/stats then other vendors might not support it. Second - trying to push counters/stats for which both the community and all the vendor agrees might proves very difficult. Second - it would be difficult to add to the current verbs API hard-coded names of counters/stats, either as strings, variables names or even enum which contains a list of names. Since that's such a good idea. I'll take the weekend to think about it and see if I can offer some kind of generic approach to solving this problem. Guy On Wed, Mar 09, 2017 at 01:37:39PM +0000, Amrani Ram wrote: >Hi All, >I find it useful to have statistics in the user-space library. >For example - >1. Number of post_sends per WR type >2. Number of failed post_sends >3. Number of polled CQs >4. Number of polled CQ errors >5. Number of times other verbs was invoked, per verb >6. Number of currently opened QPs, perhaps in each state >7. ... > >I'm not sure what mechanism to use to minimize impact on >performance. In the kernel space, for example, the 'per CPU variables' >can be used, but I'm not aware of a similar mechanism in user space. >Any ideas? >Is this is of use and benefit to anyone? >If so, perhaps something like this can be added to libibverbs. >Also of interest is the scope of the statistics. Per my understanding >libibverbs works per context that will be destroyed after the application >terminates. So I'm asking myself, and you, if it is interesting to >store statistics at a higher scope (aggregate contexts)? >Is it interesting to store statistics per-QP? >(note: currently libibverbs doesn't hold the context's QP list) >Thanks, >Ram > >-- >To unsubscribe from this list: send the line "unsubscribe linux-rdma" in >the body of a message to majordomo@xxxxxxxxxxxxxxx >More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
