Hi
can we use the write back way to use redis? only write data to redis, and
redis use the aof mode to persistent data. alpha uses an asynchronous thread to
put these 'cold data' to db and delete it from redis. alpha only read and write
with redis.
?取 Outlook for Android<https://aka.ms/ghei36>
________________________________
From: Zheng Feng <zh.f...@gmail.com>
Sent: Wednesday, August 15, 2018 10:48:34 PM
To: dev@servicecomb.apache.org
Subject: Re: Performance tuning of ServiceComb Saga Pack
Hi Willem,
It makes sense to use the redis to store the pending transactions (I assume
that you mean these are the "HOT" ones). But we could be very careful to
"write" the transaction status, and it should be stored in the database at
last. So I think we must make sure the transaction status in the redis and
the DB is consist and we SHOULD NOT lose the any status of the transaction.
How will you use the redis and the database when storing the status of
transaction ?
1. write to the redis and the redis will sync to the database later. if
failed, rollback the transaction.
2. both write to the redis and the database. if any of them failed,
rollback the transaction.
We need the more detail :)
Amos
2018-08-15 8:48 GMT+08:00 Willem Jiang <willem.ji...@gmail.com>:
> Hi,
>
> With the help of JuZheng[1][2], we managed to deploy the saga-spring-demo
> into K8s and start the Jmeter tests for it. By running the test for a
> while, the DB CPU usage is very high and the response time is up 2~3
> seconds per call.
>
> It looks like all the event are stored into the database in the same table
> and never cleaned.
> Now we are thinking use redis to store the hot data (the saga transaction
> which is not closed), and put the cold data (which is used for auditing)
> into database. In this way it could keep the event data smaller and the
> event sanner[4] can just go through the unfinished the Saga transactions to
> fire the timeout event or the compensation event.
>
> Any thought?
>
> [1]https://github.com/apache/incubator-servicecomb-saga/pull/250
> [2]https://github.com/apache/incubator-servicecomb-saga/pull/252
> [3]
> https://github.com/apache/incubator-servicecomb-saga/
> tree/master/saga-demo/saga-spring-demo
> [4]
> https://github.com/apache/incubator-servicecomb-saga/blob/
> 44491f1dcbb9353792cb44d0be60946e0e4d7a1a/alpha/alpha-core/
> src/main/java/org/apache/servicecomb/saga/alpha/core/EventScanner.java
>
> Willem Jiang
>
> Twitter: willemjiang
> Weibo: 姜宁willem
>
