RE: Is PREPARE of ecpglib thread safe? - Mailing list pgsql-hackers

From Matsumura, Ryo
Subject RE: Is PREPARE of ecpglib thread safe?
Date
Msg-id 03040DFF97E6E54E88D3BFEE5F5480F737AC3AD8@G01JPEXMBYT04
Whole thread Raw
In response to Re: Is PREPARE of ecpglib thread safe?  (Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>)
Responses Re: Is PREPARE of ecpglib thread safe?
List pgsql-hackers
Horiguchi-san

Thank you for your comment.

> A connection cannot be concurrently used by multiple threads so
> the programmer must guard connections using mutex [1] or
> friends. If it is done by a single mutex (I suppose it is
> common.), there's no race condition also on the prepared
> statement storage. I'm not sure it is explicitly aimed but I
> suppose that there's no problem in a common usage of the library.

I understand it, but current scope of StatementCache and DeclareStatementList seems not
to be limitted within each connection, isn't it?
Therefore, I thought the operation on them must be thread safe.

For example, scope of DescriptorList in descriptor.c is within thread (not connection)
by using pthread_getspecific/ pthread_setspecific().

Regards
Ryo Matsumura



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