it helps a lot! :D
On 12/26/16 12:28, John Blum wrote:
Amit-
Regarding...
/> I want to load all data on cache startup at a go./
Since you are using "/Spring/", you could easily implement a /Spring/
BeanPostProcessor [1] (BPP) for each (or all the) /Region(s)/ in which
you need to load data. I do this frequently in /Spring Data
GemFire/Geode's/ test suite when testing /Region/ data access
operations using the GemfireTemplate, /Repositories/ or things of that
nature. Clearly your BPP could use a DataSourceto load the data from
an external data store (e.g. RDBMS).
Another way to do load data on startup is to use a Geode
/Initializer/. However, this would require you to specify a snippet
of cache.xml and does not work if you specify your /Regions/ in
/Spring/ (XML/Java) config as you should when using /Spring/. I also
don't recommend using cache.xml, but is the pure, non-/Spring/ way to
invoke logic after the cache has been "fully" initialized (i.e. where
the /Regions/ have been defined in cache.xml).
See here [2] for more details. Note, the documentation talks of
"launching an application" on startup, after cache initialization, but
technically, you can do whatever you want, like load data.
I recommend the BPP.
/> How should I set it up in config to allow it to join other nodes in
cluster?/
Regardless of whether your server data node is "embedded" or not, you
can still use a Locator, or mcast to have the node join the cluster.
The "embedded" scenario, where the "application" is a GemFire Server
data node will be part of the cluster as Udo said.
This is easily achievable with...
<util:properties id="gemfireProperties">
<prop key="name">Example</prop>
<!-- Set to non-zero value to use Multicast; comment out "locators" -->
<prop key="*mcast-port*">0</prop>
<prop key="log-level">${gemfire.log-level:config}</prop>
<prop key=“*locators*”>someHost[10334]</prop>
<prop key="start-locator">localhost[1034]</prop>
</util:properties>
<gfe:cache properties-ref="gemfireProperties"/>
...
As you can see from the snippet of /Spring/ XML config above, this
application is a Geode "peer" cache (i.e. embeds a Geode data
node/server).
The "*locators*" Geode/GemFire property enables this node to connect
to a cluster. Likewise, you can use the "*mcast-port*" property
instead, however, I would recommend /Locators/ over mcast.
Additionally, you can see that I specified the "start-locator"
Geode/GemFire property, which enables me to start an embedded
Locator. Useful for testing purposes and connecting Geode data nodes
together in a cluster without a dedicated Locator, though, this
approach is less resilient if the applications/servers go down (as may
be the case in a micro-services scenario)!
/> if I start with embedded server is it required to use client pool
or is it not required?/
A "client pool" is only applicable to cache clients (i.e.
ClientCaches) on the "client-side" of the equation. "peers" find
(Locator, mcast) and communicate (TCP/UDP, JGroups) with each other
through other means once a cluster is formed.
In fact, typically, it is more common to position your
microservices-based applications as Geode cache clients (i.e.
<gfe:client-cache ...>) and have them connect to a dedicated Geode
service (i.e. cluster of Geode servers/data nodes where also, 1 or
more of those nodes are running a "CacheServer", listening for cache
clients to connect). These dedicated Geode server nodes in a cluster
constituting the service can still be configured with /Spring/, but
they typically will not contain an application-specific components
other than CacheListeners, Loaders, Writers, AEQ /Listeners/, etc.
ClientCache applications use 1 or more Pools configured to talk to the
servers in the cluster (either by way of Locator or direct server
communication). Pools can be configured with groups to target specific
members (in that group) in the cluster. Typically, members in 1 group
host a different set of Regions from another group and is a way to
separate data traffic from 1 client to another dedicated to a specific
resource/purpose (usually based on business function, etc).
On a side note, some of what you are wanting to do "scale-wise" seems
like a perfect fit for Pivotal CloudFoundry, which can auto-scale up
or down nodes in your cluster based on load and other factors.
Anyway, hope this helps!
-John
[1]
http://docs.spring.io/spring/docs/current/spring-framework-reference/htmlsingle/#beans-factory-extension-bpp
[2]
http://geode.apache.org/docs/guide/basic_config/the_cache/setting_cache_initializer.html
On Sun, Dec 25, 2016 at 11:12 PM, Amit Pandey
<[email protected] <mailto:[email protected]>> wrote:
Hey,
Thanks.
I have lots of reference data which will be loaded at start of
day. This data is not bound to change much and as such I want to
keep it loaded at the start of day. Read through will make it slow
while it is being actually accessed so I want to keep it loaded in
memory.
Also I want to have functions which will be called by clients to
do some compute and return results. Using functions should allow
me to add nodes and speed up the compute.
I have some micro services each of which will start a gemfire
node, and I want to connect, so yes I can set it up with locator.
However I have one doubt, if I start with embedded server is it
required to use client pool or is it not required?
Regards
On Mon, Dec 26, 2016 at 1:18 AM, Udo Kohlmeyer
<[email protected] <mailto:[email protected]>> wrote:
Hi there Amit,
At this stage the only way you could load all data at one go
is to write a client to connect to the db and load all in.
Another approach could be to write the same code into a
function and invoke the function at start up. But in both
cases both are manual.
To have geode servers join a cluster, you have 2 ways.
1. Connecting them up via a locator
2. Connecting them up via mcast.
Please be aware the once you connect a server to a cluster,
that server becomes an integral part of the cluster so
adding/removing servers from a cluster is not something you'd
want to do in a load-based scaling model. i.e if the load is
high, add a server and if load is low, shut down a server.
Just interest sake, what is your use case.
--Udo
On 12/24/16 05:57, Amit Pandey wrote:
Hi Guys,
I am using Spring Data Geode. I have been able to use read
and write through/ write behind. I want to load all data on
cache startup at a go.
Secondly my geode server is embedded but I want to allow it
join to other nodes. How should I set it up in config to
allow it to join other nodes in cluster?
Regards
--
-John
john.blum10101 (skype)
