RFR 8073124: Tune test and document TimSort runs length stack size increase

[David Holmes]

On 16/02/2015 6:59 PM, Lev Priima wrote:
> Thanks, David,
> Could you please push it ?

I will if Roger doesn't get to it first. It'll be 11 hours before I can 
push it.

David

> Lev
>
> On 02/16/2015 08:55 AM, David Holmes wrote:
>> On 14/02/2015 12:03 AM, Lev Priima wrote:
>>> Please review and push:
>>> http://cr.openjdk.java.net/~lpriima/8073124/webrev.00/
>>> bug: https://bugs.openjdk.java.net/browse/JDK-8073124
>>
>> I hadn't realized 8072909 had been pushed without final reviewer
>> comments being addressed. :(
>>
>> These changes seem okay. I hope they get promoted at the same time as
>> the original changeset so we don't get test failures.
>>
>> Thanks,
>> David
>>
>>> Lev
>>>
>>> On 02/13/2015 05:20 AM, David Holmes wrote:
>>>> Hi Lev,
>>>>
>>>> On 13/02/2015 2:56 AM, Lev Priima wrote:
>>>>> Christos,
>>>>>
>>>>> Test may fail on shorter arrays(page 8 of paper). For instance, on
>>>>> worst
>>>>> case, generated by test, it starts to fail on length 67108864.
>>>>> After increasing stack size of runs to merge, Arrays.sort(T[]) works
>>>>> also on maximum possible array for HotSpot JVM.
>>>>
>>>> I'd also like to see this documented somewhere in the code. Presently
>>>> there is a reference to listsort.txt but then you have to go and find
>>>> it on the web. :( At a minimum could we please add:
>>>>
>>>>  175          * computation below must be changed if MIN_MERGE is
>>>> decreased.  See
>>>>  176          * the MIN_MERGE declaration above for more information.
>>>> +             * The maximum value of 49 allows for an array up to
>>>> length
>>>> +             * Integer.MAX_VALUE-4.
>>>>
>>>>> Roger, David,
>>>>> I've updated the test (
>>>>> http://cr.openjdk.java.net/~lpriima/8072909/webrev.01/test/java/util/Arrays/TimSortStackSize2.java.html
>>>>>
>>>>>
>>>>> ) to make it more suitable for regular execution:
>>>>>
>>>>>    27  * @run main/othervm TimSortStackSize2 67108864
>>>>
>>>> This will still fail on small memory devices:
>>>>
>>>> :~> java TimSortStackSize2 67108864
>>>> Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
>>>>
>>>> as the default heap ergonomics may not be large enough. I had to add a
>>>> minimum heap of -Xmx385M to get it to run.
>>>>
>>>> Thanks,
>>>> David
>>>>
>>>>>    28  * not for regular execution on all platforms:
>>>>>    29  * run main/othervm -Xmx8g TimSortStackSize2 1073741824
>>>>>    30  * run main/othervm -Xmx32g TimSortStackSize2 2147483644
>>>>>
>>>>> Could you please push this:
>>>>> http://cr.openjdk.java.net/~lpriima/8072909/webrev.01/
>>>>> ?
>>>>>
>>>>> Lev
>>>>>
>>>>> On 02/12/2015 12:54 PM, christos at zoulas.com wrote:
>>>>>> On Feb 12, 9:57pm,david.holmes at oracle.com  (David Holmes) wrote:
>>>>>> -- Subject: Re: 8072909: TimSort fails with
>>>>>> ArrayIndexOutOfBoundsException on
>>>>>>
>>>>>> | Ok - thanks Lev!
>>>>>> |
>>>>>> | David
>>>>>>
>>>>>> For posterity can someone document this, and also the value for which
>>>>>> Integer.MAX_VALUE-4 fails?
>>>>>>
>>>>>> christos
>>>>>
>>>
>