I believe it came in on https://github.com/apache/trafficserver/pull/3246

On Wed, Dec 12, 2018 at 7:04 PM Phil Sorber <sor...@apache.org> wrote:

> Can you point me to the PR/commit on github?
>
> Thanks.
>
> On Wed, Dec 12, 2018 at 4:51 PM SUSAN HINRICHS <shinr...@ieee.org> wrote:
>
> > Fei committed the don't dump fix for jemalloc a few months back.
> >
> > On Wed, Dec 12, 2018, 4:46 PM Leif Hedstrom <zw...@apache.org wrote:
> >
> > >
> > >
> > > > On Dec 12, 2018, at 4:42 PM, Phil Sorber <sor...@apache.org> wrote:
> > > >
> > > > The problem was that we were using jemalloc as a drop in replacement
> > for
> > > > malloc/free. The DONT_DUMP issue is easy to address when using the
> > > jemalloc
> > > > APIs directly. Perhaps someone will make me a salami sandwich and I
> > will
> > > > write the patch over the holiday break. Whiskey wouldn't hurt either.
> > >
> > >
> > > I will provide both. I’ll even tap into the expensive, one of a kind
> > > Jameson irish whiskey I picked up in Cork.
> > >
> > > — Leif
> > >
> > > >
> > > >
> > > > On Wed, Dec 12, 2018 at 6:49 AM Alan Carroll
> > > > <solidwallofc...@oath.com.invalid> wrote:
> > > >
> > > >> Pushkar - based on my understanding of Fei's experiments, the issue
> > was
> > > >> doing the DONT_DUMP marking, which would cause problems with
> jemalloc.
> > > >> That's part of the effort of getting jemalloc ready.
> > > >>
> > > >> Walt - I've read through your code and I don't really the benefits.
> > It's
> > > >> definitely cleaner code, but I don't see the implementation
> advantage,
> > > >> particularly with regard to reducing pressure on heaps. E.g. "f
> there
> > > are a
> > > >> lot of smaller dynamic
> > > >> objects with short lifetimes, it will reduce thread blocking on the
> > heap
> > > >> mutex" - I don't see that. With the current implementation, in those
> > > >> circumstances there is extremely little pressure on the heap because
> > the
> > > >> objects are popping on and off thread local free lists and not
> hitting
> > > the
> > > >> underlying allocation mechanism.
> > > >>
> > > >> Also, AFAICT from the code, objects that are bigger than a pointer
> are
> > > >> allocated directly from the heap. Given that few, if any, of the ATS
> > > >> objects in question are that small, it seems like this effectively
> > > disables
> > > >> freelists. How is that better than just calling new and delete
> > directly?
> > > >>
> > > >> Another major problem is that, due the current free list
> > implementation,
> > > >> there is not much concern about constructors and destructors and
> > > depending
> > > >> on those to keep object state correct is likely to be bug prone.
> This
> > is
> > > >> going to be an issue for jemalloc as well, but if we're going to do
> > the
> > > >> work we should move all the way to no free lists at all.
> > > >>
> > > >>
> > > >> On Tue, Dec 11, 2018 at 6:05 PM Bryan Call <bc...@apache.org>
> wrote:
> > > >>
> > > >>> The freelist can be used with jemalloc, but the thought/theory is
> > that
> > > >> you
> > > >>> can turn off the freelist and use jemalloc and get similar
> > performance.
> > > >>> This needs to be validated.
> > > >>>
> > > >>> -Bryan
> > > >>>
> > > >>>> On Dec 11, 2018, at 3:18 PM, Walt Karas <wka...@oath.com.INVALID>
> > > >> wrote:
> > > >>>>
> > > >>>> I thought jemalloc is used as a drop-in replacement for the
> standard
> > > >> lib
> > > >>>> heap functions / operators.  So how can the freelist stuff not
> work
> > > >> with
> > > >>> it?
> > > >>>>
> > > >>>> On Tue, Dec 11, 2018 at 4:48 PM Bryan Call <bc...@apache.org>
> > wrote:
> > > >>>>
> > > >>>>> There is no point in cleaning up the code if the plan is to not
> use
> > > it
> > > >>> and
> > > >>>>> remove it from our codebase.  Work should be done on proving that
> > > >>> jemalloc
> > > >>>>> is valid alternative.
> > > >>>>>
> > > >>>>> If jemalloc doesn’t prove to workout, then we might look at
> > cleaning
> > > >> up
> > > >>>>> the freelist.
> > > >>>>>
> > > >>>>> -Bryan
> > > >>>>>
> > > >>>>>> On Dec 10, 2018, at 5:42 PM, Walt Karas <wka...@oath.com.INVALID
> >
> > > >>> wrote:
> > > >>>>>>
> > > >>>>>> As far as one can tell is a big limitation with code like:
> > > >>>>>>
> > > >>>>>> #if (defined(__i386__) || defined(__arm__) || defined(__mips__))
> > &&
> > > >>>>>>> (SIZEOF_VOIDP == 4)
> > > >>>>>>>
> > > >>>>>>> #define FREELIST_POINTER(_x) (_x).s.pointer
> > > >>>>>>>
> > > >>>>>>> #define FREELIST_VERSION(_x) (_x).s.version
> > > >>>>>>>
> > > >>>>>>> #define SET_FREELIST_POINTER_VERSION(_x, _p, _v) \
> > > >>>>>>>
> > > >>>>>>> (_x).s.pointer = _p;                           \
> > > >>>>>>>
> > > >>>>>>> (_x).s.version = _v
> > > >>>>>>>
> > > >>>>>>> #elif TS_HAS_128BIT_CAS
> > > >>>>>>>
> > > >>>>>>> #define FREELIST_POINTER(_x) (_x).s.pointer
> > > >>>>>>>
> > > >>>>>>> #define FREELIST_VERSION(_x) (_x).s.version
> > > >>>>>>>
> > > >>>>>>> #define SET_FREELIST_POINTER_VERSION(_x, _p, _v) \
> > > >>>>>>>
> > > >>>>>>> (_x).s.pointer = _p;                           \
> > > >>>>>>>
> > > >>>>>>> (_x).s.version = _v
> > > >>>>>>>
> > > >>>>>>> #elif defined(__x86_64__) || defined(__ia64__) ||
> > > >>> defined(__powerpc64__)
> > > >>>>>>> || defined(__aarch64__) || defined(__mips64)
> > > >>>>>>>
> > > >>>>>>> #define FREELIST_POINTER(_x) \
> > > >>>>>>>
> > > >>>>>>> ((void *)(((((intptr_t)(_x).data) << 16) >> 16) |
> > > >>>>>>> (((~((((intptr_t)(_x).data) << 16 >> 63) - 1)) >> 48) << 48)))
> //
> > > >> sign
> > > >>>>>>> extend
> > > >>>>>>>
> > > >>>>>>> #define FREELIST_VERSION(_x) (((intptr_t)(_x).data) >> 48)
> > > >>>>>>>
> > > >>>>>>> #define SET_FREELIST_POINTER_VERSION(_x, _p, _v) (_x).data =
> > > >>>>>>> ((((intptr_t)(_p)) & 0x0000FFFFFFFFFFFFULL) | (((_v)&0xFFFFULL)
> > <<
> > > >>> 48))
> > > >>>>>>>
> > > >>>>>>> #else
> > > >>>>>>>
> > > >>>>>>> #error "unsupported processor"
> > > >>>>>>>
> > > >>>>>>> #endif
> > > >>>>>>>
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>
> > > >>>>>>
> > > >>>>>> On Mon, Dec 10, 2018 at 5:02 PM Leif Hedstrom <zw...@apache.org
> >
> > > >>> wrote:
> > > >>>>>>
> > > >>>>>>>
> > > >>>>>>>
> > > >>>>>>>> On Dec 10, 2018, at 10:29 AM, SUSAN HINRICHS <
> shinr...@ieee.org
> > >
> > > >>>>> wrote:
> > > >>>>>>>>
> > > >>>>>>>> Based on Fei's measurements, the ATS freelists provide no
> > benefit
> > > >>> over
> > > >>>>>>>> jemalloc.  We are now in a position to do larger tests over
> our
> > > >>>>>>> production
> > > >>>>>>>> installs.
> > > >>>>>>>
> > > >>>>>>>
> > > >>>>>>> Agreed, that was generally what I noticed too, except, I could
> > not
> > > >> get
> > > >>>>> ATS
> > > >>>>>>> to be stable with just jemalloc. It’d eventually get unhappy,
> > but I
> > > >>>>> didn’t
> > > >>>>>>> investigate further. But this is my point, lets focus the
> efforts
> > > on
> > > >>>>> moving
> > > >>>>>>> us forward, to jemalloc, and not mess around with freelist as
> it
> > > is,
> > > >>>>>>> because it works fine as far as I can tell.
> > > >>>>>>>
> > > >>>>>>> — leif
> > > >>>>>>>
> > > >>>>>>>
> > > >>>>>
> > > >>>>>
> > > >>>
> > > >>>
> > > >>
> > > >> --
> > > >> *Beware the fisherman who's casting out his line in to a dried up
> > > >> riverbed.*
> > > >> *Oh don't try to tell him 'cause he won't believe. Throw some bread
> to
> > > the
> > > >> ducks instead.*
> > > >> *It's easier that way. *- Genesis : Duke : VI 25-28
> > > >>
> > >
> > >
> >
>

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