[Inventory] Performance of Tinkerpop3 backends
by Lukas Krejci
Hi all,
to move inventory forward, we need to port it to Tinkerpop3 - a new(ish) and
actively maintained version of the Tinkerpop graph API.
Apart from the huge improvement in the API expressiveness and capabilities,
the important thing is that it comes with a variety of backends, 2 of which
are of particular interest to us ATM. The Titan backend (with Titan in version
1.0) and SQL backend (using the sqlg library).
The SQL backend is a much improved (yet still unfinished in terms of
optimizations and some corner case features) version of the toy SQL backend
for Tinkerpop2.
Back in March I ran performance comparisons for SQL/postgres and Titan (0.5.4)
on Tinkerpop2 and concluded that Titan was the best choice then.
After completing a simplistic port of inventory to Tinkerpop3 (not taking
advantage of any new features or opportunities to simplify inventory
codebase), I've run the performance tests again for the 2 new backends - Titan
1.0 and Sqlg (on postgres).
This time the results are not so clear as the last time.
>From the charts [1] you can see that Postgres is actually quite a bit faster
on reads and can better handle concurrent read access while Titan shines in
writes (arguably thanks to Cassandra as its storage).
Of course, I can imagine that the read performance advantage of Postgres would
decrease with the growing amount of data stored (the tests ran with the
inventory size of ~10k entities) but I am quite positive we'd get competitive
read performance from both solutions up to the sizes of inventory we
anticipate (100k-1M entities).
Now the question is whether the insert performance is something we should be
worried about in Postgres too much. IMHO, there should be some room for
improvement in Sqlg and also our move to /sync for agent synchronization would
make this less of a problem (because there would be not that many initial
imports that would create vast amounts of entities).
Nevertheless I currently cannot say who is the "winner" here. Each backend has
its pros and cons:
Titan:
Pros:
- high write throughput
- backed by cassandra
Cons:
- slower reads
- project virtually dead
- complex codebase (self-made fixes unlikely)
Sqlg:
Pros:
- small codebase
- everybody knows SQL
- faster reads
- faster concurrent reads
Cons:
- slow writes
- another backend needed (Postgres)
Therefore my intention here is to go forward with a "proper" port to
Tinkerpop3 with Titan still enabled but focus primarily on Sqlg to see if we
can do anything with the write performance.
IMHO, any choice we make is "workable" as it is even today but we need to
weigh in the productization requirements. For those Sqlg with its small dep
footprint and postgres backend seems preferable to the huge dependency mess of
Titan.
[1] https://dashboards.ly/ua-TtqrpCXcQ3fnjezP5phKhc
--
Lukas Krejci
9 years, 4 months
Identification of WildFly in container in a Kube/Openshift env
by Heiko W.Rupp
Hey,
[ CC to Federico as he may have some ideas from the Kube/OS side ]
Our QE has opened an interesting case:
https://github.com/ManageIQ/manageiq/issues/9556
where I first thought WTF with that title.
But then when reading further it got more interesting.
Basically what happens is that especially in environments like
Kube/Openshift,
individual containers/appservers are Kettle and not Pets: one goes down,
gets
killed, you start a new one somewhere else.
Now the interesting question for us are (first purely on the Hawkular
side):
- how can we detect that such a container is down and will never come up
with that id again (-> we need to clean it up in inventory)
- can we learn that for a killed container A, a freshly started
container A' is
the replacement to e.g. continue with performance monitoring of the app
or to re-associate relationships with other items in inventory-
(Is that even something we want - again that is Kettle and not Pets
anymore)
- Could eap+embedded agent perhaps store some token in Kube which
is then passed when A' is started so that A' knows it is the new A (e.g.
feed id).
- I guess that would not make much sense anyway, as for an app with
three app servers all would get that same token.
Perhaps we should ignore that use case for now completely and tackle
that differently in the sense that we don't care about 'real' app
servers,
but rather introduce the concept of a 'virtual' server where we only
know
via Kube that it exists and how many of them for a certain application
(which is identified via some tag in Kube). Those virtual servers
deliver
data, but we don't really try to do anything with them 'personally',
but indirectly via Kube interactions (i.e. map the incoming data to the
app and not to an individual server). We would also not store
the individual server in inventory, so there is no need to clean it
up (again, no pet but kettle).
In fact we could just use the feed-id as kube token (or vice versa).
We still need a way to detect that one of those kettle-as is on Kube
and possibly either disable to re-route some of the lifecycle events
onto Kubernetes (start in any case, stop probably does not matter
if he container dies because the appserver inside stops or if kube
just kills it).
--
Reg. Adresse: Red Hat GmbH, Technopark II, Haus C,
Werner-von-Siemens-Ring 14, D-85630 Grasbrunn
Handelsregister: Amtsgericht München HRB 153243
Geschäftsführer: Charles Cachera, Michael Cunningham, Michael O'Neill,
Eric Shander
9 years, 4 months
Integration of APM into Hawkular Services
by Gary Brown
Hi
Hawkular APM is currently built as a separate distribution independent from other Hawkular components. However in the near future we will want to explore integration with other components, such as Alerts, Metrics and Inventory.
Therefore I wanted to explore the options we have for building an integrated environment, to provide the basis for such integration work, without impacting the more immediate plans for Hawkular Services.
The two possible approaches are:
1) Provide a maven profile as part of the Hawkular Services build, that will include the APM server. The UI could be deployed separately as a war, or possibly integrated into the UI build?
2) As suggested by Juca, the APM distribution could be built upon the hawkular-services distribution.
There are pros/cons with both approaches:
My preference is option (1) as it moves us closer to a fully integrated hawkular-services solution, but relies on a separate build using the profile (not sure if that would result in a separate release distribution).
Option 2 would provide the full distribution as a release, but the downside is the size of the distribution (and its dependencies, such as cassandra), when user only interested in APM. Unclear whether a standalone APM distribution will still be required in the future - at present the website is structured to support this.
Thoughts?
Regards
Gary
9 years, 5 months
[Inventory] What constitutes a "syncable" change of an entity?
by Lukas Krejci
Hi all,
tl;dr: This probably only concerns Mazz and Austin :)
The subject is a little bit cryptic, so let me explain - this deals with
inventory sync and what to consider a change that is worth being synced on an
entity.
Today whether an entity is update during sync depends on whether some of this
"vital" or rather "identifying" properties change. Namely:
Feed: only ID and the hashes of child entities are considered
ResourceType: only ID and hashes of configs and child operation types are
considered
MetricType: id + data type + unit
OperationType: id + hashes of contained configs (return type and param types)
Metric: id
Resource: id + hashes of contained metrics, contained resources, config and
connection config
>From the above, one can see that not all changes to an entity will result in
the change being synchronized during the /sync call, because for example an
addition of a new generic property to a metric doesn't make its identity hash
change.
I start to think this is not precisely what we want to happen during the /sync
operation.
On one hand, I think it is good that we still can claim 2 resources being
identical, because their "structure" is the same, regardless of what the
generic properties on them look like (because anyone can add arbitrary
properties to them). This enables us to do the ../identical/.. magic in
traversals.
On the other hand the recent discussion about attaching an h-metric ID as a
generic property to a metric iff it differs from its id/path in inventory got
me thinking. In the current set up, if agent reported that it changed the h-
metric ID for some metric, the change would not be persisted, because /sync
would see the metric as the same (because changing a generic property doesn't
change the identity hash of the metric).
I can see 3 solutions to this:
* formalize the h-metric ID in some kind of dedicated structure in inventory
that would contribute to the identity hash (i.e. similar to the "also-known-
as" map I proposed in the thread about h-metric ID)
* change the way we compute the identity hash and make it consider everything
on an entity to contribute (I'm not sure I like this since it would limit the
usefulness of ../identical/.. traversals).
* compute 2 hashes - 1 for tracking the identity (i.e. the 1 we have today)
and a second one for tracking changes in content (i.e. one that would consider
any change)
Fortunately, none of the above is a huge change. The scaffolding is all there
so any of the approaches would amount to only a couple of days work.
WDYT?
--
Lukas Krejci
9 years, 5 months
Approach for firebase push notification
by Anuj Garg
Hello all,
I was doubtful if we gonna provide apk of android client of hawkular
through Google play store or user will have to compile for themselves. I
assume the case to be of play store.
And if that is the case then clients can not use their own google account
to setup push notifications for alerts as configration file is needed to be
inside apk.
I suggest that hawkular can provide one instance of firebase account for it
and all the hawkular servers will use the same.
With the workflow I suggest, there will not remain the need of setting up
unified push server to provide notification.
Steps :-
- With any user creation on any hawkular serve, there will be created a
32 Byte ID that we can assume to be unique.
- Any client that sign in to that user will retrieve that string and
will register to that as topic subscription.
- When ever a new alert is created. It will fire a HTTP request to
Firebase with unique id as toopic and Server key provided by hawkular
inbuilt.
- Rest work of manupulating the recieved alert will be handled on client
side.
Please write your views on this.
Thanks
Anuj Garg
9 years, 5 months
Agent 0.20.1.Final released
by John Mazzitelli
The Hawkular WildFly Agent 0.20.1.Final has been released. Should be available from Nexus.
9 years, 5 months
Hawkular Inventory 0.17.3.Final Released
by Lukas Krejci
Hi all,
I am happy to announce the release of Hawkular Inventory 0.17.3.Final.
There are now new features but a couple of important bugfixes:
* transactions are now properly handled during /hawkular/inventory/traversal.
It should no longer happen that a traversal would return stale data.
* [HAWKULAR-1099] transaction retries actually work with Titan now (Titan
closes a transaction on failure while Inventory tried to rollback a failed
transaction, leading Titan to complain about trying to work with a closed
transaction)
* update to /traversal queries to handle /traversal/recursive (which would
give you all the entities in inventory, so don't do that ;) )
--
Lukas Krejci
9 years, 5 months
