Re: [HACKERS] Burst in WAL size when UUID is used as PK whilefull_page_writes are enabled

On Fri, Oct 27, 2017 at 11:26 AM, sanyam jain <sanyamjain22@live.in> wrote:
> Hi,
>
> I was reading the blog
> https://blog.2ndquadrant.com/on-the-impact-of-full-page-writes .
>
> My queries:
>
> How randomness of UUID will likely to create new leaf page in btree index?
> In my understanding as the size of UUID is 128 bits i.e. twice of BIGSERIAL
> , more number of pages will be required to store the same number of rows and
> hence there can be increase in WAL size due to FPW .
> When compared the index size in local setup UUID index is ~2x greater in
> size.
>

You might want to give a try with the hash index if you are planning
to use PG10 and your queries involve equality operations.

-- 
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com


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