Issue #14718 has been updated by bluz71 (Dennis B).


mperham (Mike Perham) wrote:
> Dennis, my focus for this issue is fixing the memory bloat problem that plagues 1000s of Rails apps today, not a hypothetical performance problem that might affect Guilds months or years from now.
> 
> In the future Ruby could increase arenas if additional Guilds beyond the first are allocated but I believe that M_ARENA_MAX=2 would be a good, useful solution today for non-Guild apps that upgrade to Ruby 2.6.

Sure, it is a trade-off.

All options have pros and cons; including that one. I was just making the point that `M_ARENA_MAX=2` is not a simple free and easy win, it too has negative consequences.  

Personally I don't like the prospect of a hard-coded arena count deep in the Ruby source code. It reeks of a code-smell. How was 2 decided upon, where are results to back it up? Why note 1 or 3 or 4? What happens when Ruby is run on a 20-core machine when Guilds arrive? etc.

----------------------------------------
Feature #14718: Use jemalloc by default?
https://bugs.ruby-lang.org/issues/14718#change-72025

* Author: mperham (Mike Perham)
* Status: Open
* Priority: Normal
* Assignee: 
* Target version: 
----------------------------------------
I know Sam opened #9113 4 years ago to suggest this but I'm revisiting the topic to see if there's any movement here for Ruby 2.6 or 2.7.  I supply a major piece of Ruby infrastructure (Sidekiq) and I keep hearing over and over how Ruby is terrible with memory, a huge memory hog with their Rails apps.  My users switch to jemalloc and a miracle occurs: their memory usage drops massively.  Some data points:

https://twitter.com/brandonhilkert/status/987400365627801601
https://twitter.com/d_jones/status/989866391787335680
https://github.com/mperham/sidekiq/issues/3824#issuecomment-383072469

Redis moved to jemalloc many years ago and it solved all of their memory issues too.  Their conclusion: the glibc allocator "sucks really really hard". http://oldblog.antirez.com/post/everything-about-redis-24.html

This is a real pain point for the entire Rails community and would improve Ruby's reputation immensely if we can solve this problem.



-- 
https://bugs.ruby-lang.org/

Unsubscribe: <mailto:ruby-core-request / ruby-lang.org?subject=unsubscribe>
<http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>