RFR (M): 8016749: -XX:+UseISM fails an assert(obj->is_oop()) when running SPECjbb2005

[Vladimir Kozlov]

In general it is good. Few comments about style:

Add () for (&& (>)))

if (UseLargePages && (alignment_hint > (size_t)vm_page_size())) {

In os::large_page_init() reverse condition to execute code in method instead of check and return.

Add space: //Upon

Don't convert to one line next code:

5435     if (!UseNUMA && ForceNUMA) {
5436       UseNUMA = true;
5437     }

Thanks,
Vladimir

On 7/3/13 12:41 AM, Albert Noll wrote:
> Hi Valdimir,
>
> you are right. These methods should not be called when there is no support for ISM. I added the fatal(#method_name
> should not be called on Solaris). In addition, I found more code in os_solaris.cpp that is only there to provide support
> for Solaris 8. I removed that code as well.
>
> A jprt run was successful. I also checked that large pages can still be used.
>
> Many thanks for your help,
> Albert
>
> Here is the new webrev:
> http://cr.openjdk.java.net/~anoll/8016749/webrev.02/ <http://cr.openjdk.java.net/%7Eanoll/8016749/webrev.02/>
>
>
>
> On 02.07.2013 17:14, Vladimir Kozlov wrote:
>> On 7/2/13 8:07 AM, Vladimir Kozlov wrote:
>>> Albert,
>>>
>>> reserve_memory_special() had assert which indicated that it is only called with UseISM.
>>> Look on code in runtime/virtualspace.cpp - os::reserve_memory_special() is only call when
>>> os::can_commit_large_page_memory() return false. With your changes it always return 'true' (which is correct).
>>> I think you can replace whole body of reserve_memory_special() with fatal("this obsolete method should not be called on
>>> Solaris"); or something.
>>
>> Remove 'obsolete' from the message sine the method is not obsolete on other platforms.
>>
>> Vladimir
>>
>>> The same is for release_memory_special() but, please, verify.
>>>
>>> Thanks,
>>> Vladimir
>>>
>>> On 7/2/13 6:41 AM, Albert Noll wrote:
>>>> Christian, Vladimir, thanks for your feedback.
>>>>
>>>> I added the removed flags to the ObsoleteFlag list.
>>>>
>>>> Vladimir, you are right. Removing all mpss-related code does not allow to use large pages anymore. I followed your
>>>> suggestions and replaced 'UseMPSS' with 'UseLargePages'. I also checked if large pages work with 'pmap -xs' when the
>>>> changes in webrev.01 (see below).
>>>>
>>>> Here is the new webrev:
>>>> http://cr.openjdk.java.net/~anoll/8016749/webrev.01/ <http://cr.openjdk.java.net/%7Eanoll/8016749/webrev.01/>
>>>>
>>>> A jprt run with the above changes was successful.
>>>>
>>>> Thanks again,
>>>> Albert
>>>>
>>>> On 02.07.2013 04:28, Vladimir Kozlov wrote:
>>>>> Albert,
>>>>>
>>>>> I don't think it is incorrect changes. Only UseISM is deprecated. We still use MPSS for large pages:
>>>>>
>>>>> // UseLargePages UseMPSS UseISM
>>>>> //     true      true     false => JVM will use MPSS for large page memory.
>>>>> //                                 This is the default behavior.
>>>>>
>>>>> //     true      false    false => Unless future Solaris provides other
>>>>> //                                 mechanism to use large page memory, this
>>>>> //                                 combination is equivalent to -UseLargePages,
>>>>> //                                 VM will not use large page memory
>>>>>
>>>>>
>>>>> UseMPSS is true by default and most likely it will not work without it. So you should leave current functionality but
>>>>> replace UseMPSS with UseLargePages flag checks in os_solaris.cpp.
>>>>>
>>>>> Also verify that large pages are used by java (pmap -xs) after your changes.
>>>>>
>>>>> thanks,
>>>>> Vladimir
>>>>>
>>>>> On 7/1/13 8:35 AM, Albert Noll wrote:
>>>>>> Hi,
>>>>>>
>>>>>> thanks for reviewing this patch:
>>>>>>
>>>>>> jbs: https://jbs.oracle.com/bugs/browse/JDK-8016749
>>>>>> webrev: http://cr.openjdk.java.net/~anoll/8016749/webrev.00/
>>>>>> <http://cr.openjdk.java.net/%7Eanoll/8016749/webrev.00/>
>>>>>>
>>>>>> Problem: ISM and MPSS are part of Solaris 9, and we do not support this
>>>>>> version of Solaris anymore. Instead, we use LargePages for Solaris 10+.
>>>>>>
>>>>>> Solution: Remove all code that relates to ISM and MPSS (i.e., code that
>>>>>> relates to the 'UseISM' and 'UseMPSS' flags).
>>>>>>
>>>>>> Testing: the following jprt run passes successfully.
>>>>>>
>>>>>> jprt submit -stree . -ot 'solaris.*' -emailalbert.noll at oracle.com
>>>>>>
>>>>>> Best,
>>>>>> Albert
>>>>
>