What is better approach "mysql on VM GCE" vs Google SQL Cloud - mysql

I want to use a small mysql database in order to store some data that i going to calculate on a VM of GCE (by using Talend).
After store the data on the mysql i want to connect to it by using Excel, and update some registries.
What should be the best approach, install mysql on the VM or use Google Cloud SQL?
Kind Regards

Only you can decide what better fits your needs, but you may consider the following:
Local Mysql Pros:
Faster performances. This could be important if generating a lot of queries you would need a bigger Cloud SQL instance to have similar speed.
Minor costs
Cloud SQL Pros:
High reliability. Data is backed-up without the need of taking snapshots.
Possibility to stop or delete GCE instance and keep database active.
Easier and faster to scale if required
Easily add a read replica.
Less load on the GCE
Sincerely,
Paolo

For better performance you can run your MySQL server on a virtual machine. I have tried that with the same server specifications (1 CPU, 3.75 GB memory) and it runs much better.

Related

How to identify AWS RDS Scaling conditions

I have an application that is hosted in AWS ECS and having the database in AWS RDS. I'm using a microservice-based container architecture for my application. The frontend of the application is in Angular and Backends are in Java and Python. Right now, the database size is ~1GB. The database size will increase day by day as the scraped data will be inserted daily.
Right now, some queries are taking 4-6 seconds to execute. We need to host this application to the public and there are a lot of users will be using the application. So when we load tested the application with 50 users, I found that the CPU of RDS reached 100% and some queries had taken more than 60 seconds to execute and then timed-out. Also, the CPU and memory of other microservices (frontend and backend) are normal. I have tried vertically scaling the application up to 64GB RAM and 4 vCPUs but still, this condition remains.
Is this an issue with the query or can I do anything with the database server configuration?
The RDS storage I'm using is 100GB with a general-purpose SSD. So, I guess there will be only 300 IOPS, right? I'm planning to use RDS read replicas but before that, I need to know is there anything that I need to do for improving the performance? Any database configurations etc?
I also not have a good idea about the MySQL connection count. Right now, it is using a total of 24 connections. Do I need to change the connection count also?
Query Optimisation
As Tim pointed out, try and optimise the queries. Since you have more data getting inserted, consider indexing the table and make the queries to use indexed columns if possible. also consider archiving unused old data.
number of connections
If you have control over the code, you can make use of database pools to control the number of connections that your applications can use.
CPU usage
the CPU usage is highly related to the performance of the queries, once you optimise the queries, the CPU usage should come down.
disk usage
Use the cloudwatch metrics to monitor the disk usage, based on that, you can decide on a provisioned IOPS disk.
hope this helps.

Downgrade AWS RDS Instance

I am using t2.large RDS instance, I want to downgrade to t2.micro to fit my current business. I have a few question to ask:
- How can I downgrade RDS instance without losing data and downtime ?
Thanks,
You can't really do it without downtime, but you could minimize the downtime.
The easiest option is to Modify the DB instance. This will result in downtime because a new database will be provisioned, the data will be relocated and the DNS name will be changed to point to the new instance.
Seeing that you believe a t2.micro will be sufficient for your database, it would be fair to assume that there would be times when your database is not in use so that you can perform the Modify operation. It should only take a few minutes.
Officially, the best way to modify a database without downtime is to use Multi-AZ, which can update one node while traffic is still being served by another node. However, your goal seems to be to reduce cost, rather than spending more to ensure uptime.
By the way, a t2.micro is quite limited in terms of CPU and network bandwidth. You are trying to save 21c per day, at the potential cost of having a poorly-responding database.
You can consider creating a read replica (t2.micro) of the master instance (t2.large). Once the read replica is in sync with the master instance, you can promote the read replica and then point the application towards the new master instance (which is the promoted read replica).
For reference, see:
https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_MySQL.Replication.ReadReplicas.html
https://aws.amazon.com/blogs/aws/amazon-rds-for-mysql-promote-read-replica/

MySql localhost vs Amazon RDS instance

I have surprise with some of mysql performance.
When I run simple query 'SELECT 1;' on my local host (mysql 5.6.x) using workbench, its execute in 0.000s, but the same query I ran on Amazon RDS (medium mysql 5.5.x) it tooks almost 0.094s.
I can not understand this behavior of mysql.
I would propose that you go for simplicity of maintenance and scalability (which RDS apparently provides much better than local MySQL) over performance for now.
Later on, when you get insufficient output for dollar paid for Amazon, you could start measuring carefully to find bottlenecks.
Nonetheless, if you are used to maintain private tightly packed VPS servers — local MySQL could be more simple to maintain, and you should only go for external services much later :)
The query SELECT 1 nearly requires no parsing and no table access so its execution is quick. For remote servers however there's also the time to transmit the request and shared resources like RDS are not real-time resources, so it might take a millisecond or two to get the task executed. If there's no bigger difference then just ignore this little extra time.

Amazon RDS MySQL instance performs very slow

I have published my website on Amazon EC2 (Singapore region) and I have used MySQL RDS instance for the data storage. Everything is working very fine except performance.
I seems that, my all queries, especially the select statement, is performing very slowly. If I check this issue on my local PC, there it is working very well. But when I am trying to get data from RDS instance, it is very slow. Some of the select statements takes 2-3 seconds to fetch data.
I have properly tuned up all table indexes, and normalized/de-normalized as required. I have made all necessary settings on RDS custom parameter group (eg. max_connection, buffer etc). I don't know if I am missing something, but it didn't work for me - performance didn't increase.
So, can someone please help me with this issue?
It is worth noting that, for whatever reason, MySQL query cache is OFF by default in RDS. We learned that the hard way ourselves this week.
This won't help performance of your initial query, but it may speed things up in general.
To re-enable query cache:
Log in to the RDS Console
Click on your RDS instance to view it's details
Edit the Database Parameter Group
Be sure to set both query_cache_size and query_cache_type
(Disclaimer: I am not a DBA so there may be additional things I'm missing here)
For me, it was nothing to do with MySQL but rather the instance type I was on t2.medium. The problem is I ran out of CPU credits because the load on the DB was too high and the balance kept going down until finally, I was getting far fewer credits hourly than were needed.
Here is what I saw in RDS CloudWatch under CPU Credit Usage:
If you have the same problem it may be time to switch to a different instance. Here is the list of instance types:
https://aws.amazon.com/rds/instance-types/
Hope this helps.
It is important to have your RDS and EC2 instances not just in the same region but also in the same availability zone to minimize the latency.
I had an API hosted in Ireland on EC2 and moved the Database to a MySQL cluster in Virginia USA that we had set up for another project and the round trip on every SQL query made the API unusable.
RDS MySQL performance can be increased in following ways assuming the system has more read ratio:
Use Larger instance types, they come with better NW bandwidth. Example AWS Quadruple EXL comes with 1,000 Mbps bandwidth.
Use PIOPS storage you can extract 12,500 IOPS of 16KB from MySQL DB
If lots of read is performed, add one or more Read Replica's to increase read performance
Apply standard practices like: Tune the queries, apply the indexes etc
First i highly recommend to look over these queries using
SHOW FULL PROCESSLIST
You can read more about it on SHOW FULL PROCESSLIST
This will show you the time each query take.
Then you can use
EXPLAIN
You can read more about it on EXPLAIN
This will show you if you need some enhancement on your queries
You can check where the query is taking time by making use of profiling. Use the below query:
set profiling=1
execute your select query
show profile
This will tell you about the status of the query and where the query is spending its time. If the sum of all the time returned by the profiling is less than the actual execution time of the query, then maybe other factors like Network bandwidth may be the cause of it.
Always should deploy source and rds in the same AWS availability zone for lower network latency and Should create a private endpoint link in VPC for RDS to connect RDS endpoint through the internal network instead of routing through the internet.
Reference: https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/vpc-interface-endpoints.html
I found that after migrating to RDS all my database Indexes are gone! They weren't migrated along with the schema and data. Make sure you're indexes are there.

Using ElastiCache with RDS for improving read/write performance

I am using RDS on amazon with a MySQL interface. My application runs on EC2 nodes and read/update the database, but the number of reads and writes are too many and that reduces performance. Most of the time the number of connections exceed the allowed limit.
I was considering using Elasticache to improve performance, however I did not find resources on web, how to configure database to use this effectively.
Is this the best way to improve my read/write performance?
Any suggestions?
You can't just "turn on" memcache. You need to write code that interacts with memcache, such that your database query results are cached in memcache. Take a look at this users guide -- I think it will give you a good idea for how memcache is used:
http://www.memcachier.com/documentation/memcache-user-guide/
Performance is related to the type and structure of the queries used, so there might be some room for optimization. Maybe you can provide more details about the exact queries used. However, you could tackle this from a different angle - if you had an auto scaling capability, you could simply scale up your database to additional machines if needed, so you could accommodate an infinite number of connections even without any performance optimization (of course if you optimize it will improve performance). This is not possible on RDS, but there are at least two other cloud DB providers running on EC2 that I'm aware of which offer auto scaling - www.xeround.com and www.enterprisedb.com.
You can use elasticache as a second level cache for your rds db. If you use java you can use the hibernate-memcached lib. But you still need to configure how and what to cache in the second level cache depending on your data.
Additionally you could use read replica at RDS least to get split the read traffic.
(What instance type are you using, you saw that they have different i/o capacities?)