Hi,
On Sep 29, 2022, 09:38 +0800, Xiaoran Wang <wxiao...@vmware.com>, wrote:
> Hi,
> The max size for the shmem hash table name is SHMEM_INDEX_KEYSIZE - 1. but
> when the caller uses a longer hash table name, it doesn't report any error,
> insteadit just uses the first SHMEM_INDEX_KEYSIZE -1 chars as the hash table
> name.
> I created some shmem hash tables with the same prefix which was longer
> thanSHMEM_INDEX_KEYSIZE - 1, and the size of those hash tables were the
> same,then only one hash table was created. But I thought those hash tables
> were createdsuccessfully.
> I know this is a corner case, but it's difficult to figure it out when run
> into it. So I addan assertion to prevent it.
>
> Thanks,Xiaoran
Seems Postgres doesn’t have a case that strlen(name) >= SHMEM_INDEX_KEYSIZE(48).
The max length of name I found is 29:
```
ShmemInitHash("Shared Buffer Lookup Table”
```
But it will help for other Databases built on Postgres or later Postgres in
case of forgetting to update SHMEM_INDEX_KEYSIZE
when new shmem added with a name longer than current SHMEM_INDEX_KEYSIZE.
And we don’t have such assertion now.
So, +1 for the patch.
Regards,
Zhang Mingli
