5 ms·

1 thread per connection??? Not doing continual GC in a separate thread and instead taking 7 seconds and blocking everything? What is this the 1990s?

by axod 16y ago

pg 16y ago
Feel free to fork MzScheme and replace the garbage collector with a new one that runs continuously.
- jhrobert 16y ago
  There is no such thing as a free lunch
- axod 16y ago
  Surely there's a way to target the JVM? I'd trust my life on the JVM, it's pretty battle tested, and the GC is simply awesome.
  - defen 16y ago
    > I'd trust my life on the JVM You sure you want to do that? :-) > Java technology is not fault tolerant and is not designed, manufactured, or intended for use or resale as on-line control equipment in hazardous environments requiring fail-safe performance, such as in the operation of nuclear facilities, aircraft navigation or communication systems, air traffic control, direct life support machines, or weapons systems, in which the failure of Java technology could lead directly to death, personal injury, or severe physical or environmental damage http://technet.microsoft.com/en-us/library/cc976720.aspx http://technet.microsoft.com/en-us/library/cc976720.aspx
    - axod 16y ago
      Yeah I'd trust my life on it. I've had java processes running for several months without issue. The hardware fails before the jvm does. I wouldn't trust anything from microsoft though.
    - projectileboy 16y ago
      I've helped build rail control systems that run on Java, so you're probably trusting your life to Java daily without knowing it.
  - shortlived 16y ago
    The JVM really is great and the garbage collecting outstanding. Anyone who has written a real high performance app can tell you that.
- acangiano 16y ago
  Do you ever question the choice of MzScheme?
  - pg 16y ago
    It had to be some dialect of Lisp with continuations, which meant Scheme, and MzScheme seemed the best. Our first version ran on Scheme48, but that was such a pain that we switched.
- marcamillion 16y ago
  I love this response. Would be really interested in a follow-up from axod (or by pg about axod's version). It's easy to criticize, but let's see what happens when the pedal hits the metal.
  - axod 16y ago
    My response TBH, would be that there is no point spending months tweaking the engine of a ford to try and get it to perform like a porche. Just get a porche in the first place. I don't value "being able to write it in my favorite language" at all. From what I've read, pg does. To the extent that the product suffers. There would be absolutely no point me trying to improve mzScheme when you can do exactly the same job in other languages/platforms, and the user doesn't care/know the difference. HN could be rewritten in a weekend, in PHP/python/whatever and we wouldn't be sitting here waiting for pages to load. (I run Mibbit, which handles a few thousand HTTP requests a second, on VPS level hardware. In Java).
    - jmtulloss 16y ago
      Neither Python nor PHP run garbage collection continuously in a separate thread. Python is reference counted, and as far as I know PHP is too.
      - axod 16y ago
        But I'd bet both of them perform far better than MzScheme. In any event, it's a "solved problem". The sheer amount of time and effort going into this is silly. Just pick a better language/platform and use it.
        marcamillion 16y ago
        I guess the point is, axod, if you aren't willing to backup talk with action, it might be best to think about what you say before you say it. Don't slam something saying I could do better, and then have your bluff called. Makes you look silly. This applies to even if the person calling your bluff was NOT pg.
jlouis 16y ago
Let me add that one "thread" per connection works in Erlang for up to 80k connections easily. And since each "thread" is actually a process and each with their own GC, long pause-times are never a problem. It is not the year, but the naivety that is the problem here, if any.

1 thread per connection??? Not doing continual GC in a separate thread and instead taking 7 seconds and blocking everything? What is this the 1990s?

by axod 16y ago

1 thread per connection??? Not doing continual GC in a separate thread and instead taking 7 seconds and blocking everything? What is this the 1990s?

pg 16y ago

Feel free to fork MzScheme and replace the garbage collector with a new one that runs continuously.

jhrobert 16y ago
There is no such thing as a free lunch
axod 16y ago
Surely there's a way to target the JVM? I'd trust my life on the JVM, it's pretty battle tested, and the GC is simply awesome.
- defen 16y ago
  > I'd trust my life on the JVM You sure you want to do that? :-) > Java technology is not fault tolerant and is not designed, manufactured, or intended for use or resale as on-line control equipment in hazardous environments requiring fail-safe performance, such as in the operation of nuclear facilities, aircraft navigation or communication systems, air traffic control, direct life support machines, or weapons systems, in which the failure of Java technology could lead directly to death, personal injury, or severe physical or environmental damage http://technet.microsoft.com/en-us/library/cc976720.aspx http://technet.microsoft.com/en-us/library/cc976720.aspx
  - axod 16y ago
    Yeah I'd trust my life on it. I've had java processes running for several months without issue. The hardware fails before the jvm does. I wouldn't trust anything from microsoft though.
  - projectileboy 16y ago
    I've helped build rail control systems that run on Java, so you're probably trusting your life to Java daily without knowing it.
- shortlived 16y ago
  The JVM really is great and the garbage collecting outstanding. Anyone who has written a real high performance app can tell you that.
acangiano 16y ago
Do you ever question the choice of MzScheme?
- pg 16y ago
  It had to be some dialect of Lisp with continuations, which meant Scheme, and MzScheme seemed the best. Our first version ran on Scheme48, but that was such a pain that we switched.
marcamillion 16y ago
I love this response. Would be really interested in a follow-up from axod (or by pg about axod's version). It's easy to criticize, but let's see what happens when the pedal hits the metal.
- axod 16y ago
  My response TBH, would be that there is no point spending months tweaking the engine of a ford to try and get it to perform like a porche. Just get a porche in the first place. I don't value "being able to write it in my favorite language" at all. From what I've read, pg does. To the extent that the product suffers. There would be absolutely no point me trying to improve mzScheme when you can do exactly the same job in other languages/platforms, and the user doesn't care/know the difference. HN could be rewritten in a weekend, in PHP/python/whatever and we wouldn't be sitting here waiting for pages to load. (I run Mibbit, which handles a few thousand HTTP requests a second, on VPS level hardware. In Java).
  - jmtulloss 16y ago
    Neither Python nor PHP run garbage collection continuously in a separate thread. Python is reference counted, and as far as I know PHP is too.
    - axod 16y ago
      But I'd bet both of them perform far better than MzScheme. In any event, it's a "solved problem". The sheer amount of time and effort going into this is silly. Just pick a better language/platform and use it.
      - marcamillion 16y ago
        I guess the point is, axod, if you aren't willing to backup talk with action, it might be best to think about what you say before you say it. Don't slam something saying I could do better, and then have your bluff called. Makes you look silly. This applies to even if the person calling your bluff was NOT pg.

jlouis 16y ago

Let me add that one "thread" per connection works in Erlang for up to 80k connections easily. And since each "thread" is actually a process and each with their own GC, long pause-times are never a problem. It is not the year, but the naivety that is the problem here, if any.