Question on LWLockMode in dsa.c - Mailing list pgsql-hackers

From Masahiko Sawada
Subject Question on LWLockMode in dsa.c
Date
Msg-id CAD21AoALgrU2sGWzgq+6G9X0ynqyVOjMR5_k4HgsGRWae1j=wQ@mail.gmail.com
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Responses Re: Question on LWLockMode in dsa.c
Re: Question on LWLockMode in dsa.c
List pgsql-hackers
Hi,

While working on radix tree patch[1], John Naylor found that dsa.c
doesn't already use shared locks even in dsa_dump(). dsa_dump() seems
a pure read-only function so I thought we could use a shared lock mode
there. Is there any reason to use exclusive mode even in dsa_dump()?

Ultimately, since we're trying to add a new function
dsa_get_total_size() that just returns
dsa_area_control.total_segment_size and therefore would also be a
read-only function, I'd like to find out the correct lock mode there.

Regards,

[1] https://www.postgresql.org/message-id/CANWCAZYYzoKp_4%2B1m5mn-TRD62BTwom8iLXLOWMsHkkwFi%3Drzg%40mail.gmail.com

-- 
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com



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