+1 @Jake, great implementation of storing the Atmoic values in a region.
Not having much experience with Hazelcast's Atomic implementation... I
would assume this is both a server and client-side construct.
That said, I would model the Atomics, to be persisted in a Replicate
Region on the server. In addition to that, depending on paranoia, this
could be a Replicate region with GLOBAL scope. This way the
create/update needs to lock the object within the region, over all
servers, before updating. But if you don't want to take the perf hit,
DISTRIBUTED_SYNC is a good second option.
As for the client side implementation, a Proxy region for simple
read-through semantics. If performance is key, maybe a CACHING_PROXY
region with subscriptions enabled. This way the Atomic values are always
updated on client-side and any client atomic lookup is "local" rather
than over the wire to the server.
--Udo
On 7/17/17 09:09, Jacob Barrett wrote:
There isn't anything provided by the Geode project but it is fairly
easy to implement. Having experimented with it internally some time
ago it really came down to utilizing the check and set map operations.
Consider AtomicInteger.comparAndSet():
public boolean compareAndSet(final Integer expect, final Integer
update) {
return region.replace(name, expect, update);
}
Then all other operations are something like this:
public final Integer getAndIncrement() {
for (;;) {
final Integer current = get();
if (compareAndSet(current, increment(current)))
return current;
}
}
Keep in mind that with any compare and set type operation the more
contention for the same resource the more often it will fail meaning
that atomic inc/dec operations may loop frequently. Many round trips
back to the server could make this very expensive.
An alternative would be to pair client side AtomicInteger with a
function on the server such that the inc/dec/set operations are sent
to the server to be resolved and the final result sent back to the
client. I have not experimented with this solution myself.
-Jake
On Sun, Jul 16, 2017 at 8:16 AM Amit Pandey <[email protected]
<mailto:[email protected]>> wrote:
Hi Guys,
We had a hazelcast app we want to port to geode. There are some
usages of AtomicLOng of hazelcast which we need to port, is there
a best practice/alternative to achieve the same in Apache Geode?
regards
