Re: [HACKERS] Parallel COPY FROM execution - Mailing list pgsql-hackers

From Robert Haas
Subject Re: [HACKERS] Parallel COPY FROM execution
Date
Msg-id CA+TgmoafL=h5cqbV+-LQ59Eu4uaPhYCzJCTPSifrHyziQCpmfA@mail.gmail.com
Whole thread Raw
In response to Re: [HACKERS] Parallel COPY FROM execution  (Alex K <kondratov.aleksey@gmail.com>)
Responses Re: [HACKERS] Parallel COPY FROM execution  (Daniel Gustafsson <daniel@yesql.se>)
List pgsql-hackers
On Fri, Aug 11, 2017 at 9:55 AM, Alex K <kondratov.aleksey@gmail.com> wrote:
> - I have used both Latch and ConditionalVariable for the same
> purpose–wait until some signal
>   occurs–and for me as an end user they perform quite similar. I
> looked into the condition_variable.c
>   code and it uses Latch and SpinLock under the hood. So what are
> differences and dis-/advantages
>   between Latch and ConditionalVariable?

A ConditionVariable lets you signal the processes that are waiting
without needing to know in advance exactly which processes those are.
If you use latches directly, you'll have to somehow keep track of
which processes need to be signaled.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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