Re: How to know how much CPU, RAM is used by existing 1 database

I hope the below link helps...

https://www.enterprisedb.com/blog/monitor-cpu-and-memory-percentage-used-each-process-postgresqlppas-91

On 10/26/22, Rob Sargent <robjsargent(at)gmail(dot)com> wrote:
> On 10/26/22 08:26, Yi Sun wrote:
>>
>>
>> On Wed, 26 Oct 2022 at 18:10, jian he <jian(dot)universality(at)gmail(dot)com>
>> wrote:
>>
>>
>>
>> On Wed, Oct 26, 2022 at 11:07 AM Yi Sun <yinan81(at)gmail(dot)com> wrote:
>>
>> Hi Guys,
>>
>> Who can help me with this please? I researched but still no
>> result yet, thank you
>>
>> On Tue, 25 Oct 2022 at 16:30, Yi Sun <yinan81(at)gmail(dot)com> wrote:
>>
>> Hi,
>>
>> There are many databases in our production patroni cluster
>> and it seems it is overloaded, so we decide to migrate the
>> busiest database to a new patroni cluster.
>>
>> pgwatch2 is implemented, how to know how much CPU, RAM is
>> used by the database please? Then we can use it to prepare
>> the new patroni cluster hardware. Thank you
>>
>> Best regards
>> Dennis
>>
>>
>> manual:
>> https://www.postgresql.org/docs/current/runtime-config-resource.html|
>> |
>> |except |min_dynamic_shared_memory| (|integer|)|
>> |all other parameters are used to cap the memory. almost all
>> parameters mentioned "database server" which means it's on cluster
>> level.
>> |
>> |
>> |
>> |
>> |
>> --
>>  I recommend David Deutsch's <<The Beginning of Infinity>>
>>
>>   Jian
>>
>>
>>
>>  Hi Jian he
>>
>> Thank you for your reply
>>
>> The parameters are on cluster level, so we still can not know how much
>> memory is used in a specific database, for example, total memory is 64GB
>> 1. How to get how much memory is used on cluster level? For example 40GB
>> 2. How to get how much memory is used in a specific database? For
>> example 30GB, then we can prepare the new patroni cluster 32GB is enough
>>
>> Thank you
>> Dennis
> You can see connection with pg*backend* functions.  You can log
> connections to see which db is most commonly accessed. You can log sql
> to see which table are being touched.  You'll have to assume a
> correlation to CPU/disc usage.  What have you tried?