Oren, you can find documentation on the Stats over HTTP plugin can be found
here:
https://docs.trafficserver.apache.org/en/latest/admin-guide/plugins/stats_over_http.en.html#admin-plugins-stats-over-http

On Sun, Dec 31, 2017 at 1:35 AM, Oren Shemesh <[email protected]> wrote:

> Thanks Ryan, Robert and Dave for your responses.
>
> Dave, can you send a pointer to any documentation/text available regarding
> 'Stats over HTTP' ?
>
> I believe I can consider the overall response to the change I am proposing
> as positive :-)
>
> Robert, from my experience I would like to avoid adding additional
> configurations to a system, in cases where the system can auto-detect the
> proper configuration.
> Any configuration added is another chance for someone making a mistake.
>
> With the proposal I have made, so configuration is needed: TM auto-detects
> the type of astats information (DS name / entire DS domain) based on a
> single 'if' statement which queries a single scalar value.
> This also means that, assuming my proposed code change is valid, there can
> be no performance issues.
>
> Also, I do not know what 'Stats over HTTP' is, but I hope it keeps the job
> of classifying Client HTTP transactions to a DS in the cache (ATS in our
> case), avoiding the need to re-classify it in TM.
>
> (Note: In my mind, the fact that TM currently does this job, based on a
> *single* hostName regex per DS, makes the entire feature of having multiple
> regexps per DS very limited in use. Which is a shame, based on the effort
> invested in the DB model, TO API, and TR code).
>
> Thanks a lot guys !
>
>
> On Sat, Dec 30, 2017 at 7:33 PM, Dave Neuman <[email protected]> wrote:
>
> > Hi Oren,
> > Sorry for the slow response, I think what you are proposing sounds
> > reasonable, so +1.  I would, however, like to make sure that we aren't
> > affecting the performance of TM too much in terms of both CPU usage (with
> > 1000+ caches) and time to poll all caches/aggregate statistics.
> >
> > Additionally, I don't think we should be adding new functionality to
> astats
> > at all. The plan is to move towards the Stats Over HTTP plugin in the
> > future, so we should focus on making Traffic Monitor do what we need it
> to
> > do now, and add new functionality to Stats over HTTP if it doesn't
> > currently exist.  I do think it would be nice to have Traffic Monitor
> > support some sort of canonical stats interface instead of
> > astats/stats_over_http, and I am sure there are several other features
> > would be nice to have as well, but I don't think we should be muddying
> the
> > waters with that right now.
> >
> >
> > On Wed, Dec 27, 2017 at 12:24 PM, Robert Butts <[email protected]
> >
> > wrote:
> >
> > > I'd be +1 if we extend Astats/stats_over_http to have the DS name.
> > >
> > > It's easy to extend the Monitor to get the name from a field, if it's
> > > available. And it should be faster than the current method. But, Astats
> > > doesn't currently support it, and in fact, I don't believe ATS has a
> good
> > > way to associate an identifier (DS name) with a Remap Rule. Can anyone
> > > confirm?
> > >
> > > That said, if we're extending `stats_over_http`, I'd really like to see
> > it
> > > extended to serve CSV (ideally with the DS name in a field, as above),
> > when
> > > the request has an `Accept: text/csv` header. Astats only has a single
> > > level of JSON, and they're all numbers. So there's no reason to use
> JSON
> > > over CSV, and CSV is drastically simpler and faster to parse.
> Especially
> > if
> > > we break each `.` component of the stat into its own CSV field. The
> > Monitor
> > > is CPU-bound, so there's a good chance we'd see a noticeable
> performance
> > > improvement, which translates to a tangible poll time improvement.
> > >
> > > Also @orens if we can't reasonably extend ATS Astats, we can still
> > support
> > > your use case for your own cache, by having a separate code path in the
> > > Monitor for your "stats", and adding a "stats type" number or enum to
> the
> > > Server table (or ideally a new table for "cache servers", since it only
> > > applies to caches). So, the Monitor would look at that field (possibly
> > > adding it to `monitoring.json` or `CRConfig.json`), to determine how to
> > > parse a given server's stats.
> > >
> > > We've discussed a "stat version" field anyway, for different Astats
> > > versions. For example, we're looking into combining the System stats
> into
> > > the Ats key, and we'd also like to be able to experiment with different
> > > formats (CSV, Protobuf, etc). I think it's a good feature for the CDN
> in
> > > general, to make stat polling more flexible.
> > >
> > >
> > > On Wed, Dec 27, 2017 at 12:21 PM, Durfey, Ryan <
> [email protected]>
> > > wrote:
> > >
> > > > Oren,
> > > >
> > > > This is a great conversation to have. I can’t speak to the best
> > solution,
> > > > but allowing our servers to have a single SSL cert that could be
> shared
> > > > across delivery services would save us a lot of time, money, and
> > > > operational resources. From a product perspective this would be
> highly
> > > > beneficial to the platform especially since all services are
> eventually
> > > > moving to SSL.
> > > >
> > > > Key Benefits:
> > > >
> > > >   1.  Instant Service Builds: All new services could use SSL
> > immediately,
> > > > no 2-3 business day delays in ordering SSL certs.
> > > >      *   This gets us a step closer to instant SSL service builds
> > without
> > > > the need to implement something like “letsencrypt”.
> > > >   2.  Operations Load: Reducing the management of a constant flow of
> > > > orders and renewals for SSL certs would save operations resources and
> > > time.
> > > >   3.  Cost Reduction: A reduction in SSL certs equates to reduction
> in
> > > > purchase and renewal costs.
> > > >
> > > >
> > > >
> > > > Ryan Durfey    M | 303-524-5099
> > > > CDN Support (24x7): 866-405-2993 or [email protected]<mailto:
> > > > [email protected]>
> > > >
> > > >
> > > > From: Oren Shemesh <[email protected]>
> > > > Reply-To: "[email protected]" <
> > > > [email protected]>
> > > > Date: Wednesday, December 27, 2017 at 2:49 AM
> > > > To: "[email protected]" <
> > > > [email protected]>
> > > > Subject: Two different Delivery Services using the same host regexp:
> A
> > > > suggested Traffic Monitor code change
> > > >
> > > > Hi TC Dev people,
> > > >
> > > > We would like to avoid having to issue a specific SSL certificate for
> > > every
> > > > DS, as is needed today.
> > > >
> > > > (Reminder: Every DS needs a separate certificate because The domains
> > used
> > > > by the DS are tr.<ds-name>.<cdn-domain> and
> > > > <cache-name>.<ds-name>.<cdn-domain>, and wild-card certs support
> only
> > a
> > > > single *, so every cert is issued to *.<ds-name>.<cdn-comain>, which
> > > makes
> > > > it DS-specific).
> > > >
> > > > When configuring two different DSes to use the same host regexp, and
> > > > configuring additional path regexps to differentiate between them, it
> > is
> > > > possible to overcome this issue.
> > > >
> > > > For example: DS 'my-ds1' can have host regexp .*\.my-ds\..* , and
> path
> > > > regexp /ds1/.* (Both with order 0), and DS 'my-ds2' has the same host
> > > > regexp and path regexp /ds2/.*.
> > > >
> > > > This makes TR redirect requests of the form
> > > > tr.my-ds.<cdn-domain>/ds1/<whatever> to
> > > > <cache-name>.my-ds.<cdn-domain>/ds1/<whatever>, do the same for
> > > > tr.my-ds.<cdn-domain>/ds2/<whatever>, and respond with '503 service
> > > > unavailable' to requests to tr.my-ds.<cdn-domain> which do not start
> > with
> > > > /ds1/ or /ds2/.
> > > >
> > > > So with TR, So far so good.
> > > >
> > > > ATS can also differentiate between the DSes based on the path, so
> there
> > > is
> > > > no problem there as well.
> > > >
> > > > However, there is a problem with Traffic Monitor:
> > > >
> > > > Because astats sends per-DS info based on the origin name, TM
> requires
> > > that
> > > > every DS has a unique host regexp (See
> > > > https://github.com/apache/incubator-trafficcontrol/blob/
> > > > 3e3a5f41d482a065f46ef287b347e66d7d205d82/traffic_monitor/
> > > > todata/todata.go#L234
> > > > ).
> > > > This is so that TM can map origin names from astats back to a DS.
> > > >
> > > > So, I would like to make a small change to the TM code:
> > > >
> > > > If the astats info contains only a single host name, assume it is
> > already
> > > > the DS name.
> > > >
> > > > (This would be implemented in  <goog_1101383350>
> > > > https://github.com/apache/incubator-trafficcontrol/blob/
> > > > 3e3a5f41d482a065f46ef287b347e66d7d205d82/traffic_monitor/
> > > > cache/cache.go#L419
> > > > :
> > > >
> > > > if len(statParts) == 2 { // [0] is DS name, [1] is statName
> > > > ds = statParts[0]
> > > > }
> > > > else {
> > > > ... existing code which uses statsParts[0:len(statsParts)-1]
> > > > }
> > > >
> > > > Obviously, the ds should be checked against the list of all DSes to
> > make
> > > > sure it is valid, I wrote this code line just to demonstrate the
> idea).
> > > >
> > > > Of course, the astats plugin for ATS might not support this today (I
> am
> > > not
> > > > sure), but a different cache (Hint: Qwilt cache) has no problem
> > reporting
> > > > the astats information per DS name.
> > > > If needed, the astats code could be improved to do that, as well.
> > > >
> > > > I believe that this change, while being very small and unobtrusive,
> > would
> > > > make the information passed from caches to TM 'cache vendor
> agnostic',
> > > > while also eliminating the need to re-classify URLs into DS (Which is
> > > what
> > > > happens today in TM), hence it is a good step in a good direction.
> > > >
> > > > Any comments / opinions, please ?
> > > >
> > > > --
> > > >
> > > > *Oren Shemesh*
> > > > Qwilt | Work: +972-72-2221637| Mobile: +972-50-2281168 |
> > [email protected]
> > > > <mailto:[email protected]>
> > > > <[email protected]<mailto:[email protected]>>
> > > >
> > > >
> > >
> >
>
>
>
> --
>
> *Oren Shemesh*
> Qwilt | Work: +972-72-2221637| Mobile: +972-50-2281168 | [email protected]
> <[email protected]>
>

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