I was wondering about how deepstream decides to store an info in cache vs database if both of them are configured. Can this be decided by the clients?
Also, when using redis will it provide both cache and database functionality? I would be using amazon elastic cache with redis backend for the same.
It stores it in both, first in the cache in a blocking way and outside the critical path in the database in a non-blocking way.
Here's an animation illustrating this.
You can also find more information here: https://deepstream.io/tutorials/core/storing-data/
Related
As we can persist cache data in Apache Ignite by enabling persistanceEnabled property. Is there a similar way we can store audit events as well, i.e. when we restart ignite server, all cache events must also be retained as they are currently lost on a server restart.
I am open to any other better approach for auditing via Ignite. I basically want to store all audit operations (especially INSERT,UPDATE) which we can review(fetch) later in the future?
You would need to implement your own EventStorageSpi.
Am reading people having trouble with using rediscache in azure functions on consumption plan.
please advise best practice for using caching in azure functions 2.0
my rediscache will be used by api's as well as azure functions (consumption plan). since connection object is supposed to be singleton and reused in case of functions on every request it will create new connection will this create problems ?
Please be aware of the various limitations for Azure Redis Cache performance per pricing tier, especially SSL and Non-SSL connections per second. Please also be aware of the benefits + behaviors of using the StackExchange.Redis configuration options.
We are using kong api gateway as a single gateway for all apis. we are facing latency issue with few of our api's (1500-2000ms). later when we checked, latency was being created because of the "rate limiting" plugin. When we disable the plugin, latency improves and the response is same as what we get directly from IP (close to 300ms approx).
I m trying to setup redis node to cache database queries, I m not sure how we can configure kong to read from redis itself. how we can cache the database queries to redis node.
We are using postgresql for kong.
I think maybe you are trying to do a couple different things at once.
First, rate-limiting: what is the value for your config.policy parameter? The Kong documentation has three values: "local (counters will be stored locally in-memory on the node), cluster (counters are stored in the datastore and shared across the nodes) and redis (counters are stored on a Redis server and will be shared across the nodes)."
If you are seeing high latency, and your config.policy is set to cluster or redis, it might be due to latency between Kong and postgres/redis (depending on what policy you're using). If you are using rate-limiting just to prevent abuse, using the 'local' policy is faster. (There's more about this at the Kong documentation.)
The other question is about caching: Kong Enterprise has a built-in caching plugin, but for Kong Community, since it's built on top of Nginx, you can do caching with Nginx. This link might help you.
There is a community custom plugin out there that enables the use of caching with redis without the need to use the Kong Enterprise -> https://github.com/globocom/kong-plugin-proxy-cache
Maybe you could combine that with rate limiting to achieve the desired latency performance or use this plugin as inspiration.
Is it possible to persist the ignite cache on local file system?
I need to perform cache operations like insert, update, delete on my look up data.
But this has to be persisted on local file system of the respective nodes to survive the data even after restart of the ignite cluster.
Alternatively I was able to persist the data on MySQL database.
But I'm looking for a persistence solution that works independent of databases and HDFS.
Ignite since version 2.1 has it own native Persistence. Moreover, it has advantages over integration with 3rd party databases.
You can read about it here: https://apacheignite.readme.io/docs/distributed-persistent-store
I am going to use redis as the web cache for geoserver, so I need to understand the database connection in geoserver. I have imported geoserver in Eclipse, and there are two projects named gs-sec-jdbc and gs-web-sec-jdbc. I do not know what the “sec" means and what are the differences between these two projects. Any help or tutorial is appreciated！ Thank you !
These two modules are part of the security subsystem (gs-web-sec-jdbc is the web based user interface). They are almost certainly not the modules you are looking for.
If you intend to use redis to store WMS output images then you need to look at how GeoWebCache works.
If you want to provide a cache between GeoServer and a JDBC database then you will need to explore GeoTools' JDBC datastore mechanism.