From tom@@@k@||ber@ @end|ng |rom gm@||@com  Mon Apr 15 08:44:22 2019
From: tom@@@k@||ber@ @end|ng |rom gm@||@com (Tomas Kalibera)
Date: Mon, 15 Apr 2019 08:44:22 +0200
Subject: [Rd] SUGGESTION: Settings to disable forked processing in R,
 e.g. parallel::mclapply()
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On 4/13/19 12:05 PM, I?aki Ucar wrote:
> On Sat, 13 Apr 2019 at 03:51, Kevin Ushey <kevinushey at gmail.com> wrote:
>> I think it's worth saying that mclapply() works as documented
> Mostly, yes. But it says nothing about fork's copy-on-write and memory
> overcommitment, and that this means that it may work nicely or fail
> spectacularly depending on whether, e.g., you operate on a long
> vector.

R cannot possibly replicate documentation of the underlying operating 
systems. It clearly says that fork() is used and readers who may not 
know what fork() is need to learn it from external sources. 
Copy-on-write is an elementary property of fork().

Reimplementing mclapply to use PSOCK does not make sense -- if someone 
wants to write code that can be used both with PSOCK and FORK, there is 
the cluster API in parallel for that.

Tomas



[Rd] SUGGESTION: Settings to disable forked processing in R, e.g. parallel::mclapply()
Tomas Kalibera