RFR: 8146879: Add option for handling existing log files in UL

[Marcus Larsson]

Hi,

On 2016-03-11 15:35, Bengt Rutisson wrote:
>
> Hi Marcus,
>
> On 2016-03-11 15:21, Marcus Larsson wrote:
>> Third time's the charm.
>>
>> Webrev:
>> http://cr.openjdk.java.net/~mlarsson/8146879/webrev.03/
>
> I had a quick look at the code changes. It is not really my area of 
> the code, so I'll leave to someone else to formally review it.
>
> However, I downloaded the patch a played a bit with the logging. This 
> is much more like the way I would like it! Thanks!
>
> So, from a functional perspective this looks good to me.
>

Thanks for the feedback!

Marcus

> Thanks,
> Bengt
>
>>
>> This patch makes log file rotation the default. Default thresholds 
>> are 5 rotated files with a target size of 20MiB. Truncating behavior 
>> can be achieved by setting filecount to 0 
>> (-Xlog::myfile.log::filecount=0).
>>
>> If a log file already exists during log file initialization it will 
>> be rotated. If any of the target file names (file.0 to file.4 in the 
>> default case) are available, that filename will be used for the 
>> existing log. If all names are taken the VM will attempt to overwrite 
>> the oldest file.
>>
>> This should prevent unlimited log file creations and avoid accidental 
>> loss of log files from previous runs. The default thresholds (5 
>> files, 20MiB each) is just a suggestion. If you think it should be 
>> higher/lower let me know.
>>
>> Tested with included internal VM tests through RBT.
>>
>> Thanks,
>> Marcus
>>
>> On 2016-03-01 15:05, Marcus Larsson wrote:
>>> Hi,
>>>
>>> After some offline discussions I'm withdrawing this patch. I will 
>>> instead investigate if I can achieve similar behavior using log 
>>> rotation as the default.
>>>
>>> Thanks,
>>> Marcus
>>>
>>> On 03/01/2016 12:11 PM, Marcus Larsson wrote:
>>>> Hi again,
>>>>
>>>> Taking a different approach to this.
>>>>
>>>> New webrev:
>>>> http://cr.openjdk.java.net/~mlarsson/8146879/webrev.01/
>>>>
>>>> Existing files will now by default be renamed/archived with a .X 
>>>> suffix where X is the lowest number such that the resulting file 
>>>> name is available (jvm.log becomes jvm.log.0). A mode option for 
>>>> controlling this behavior has been added as well. It can be set to 
>>>> archive, append, or truncate (i.e. -Xlog::jvm.log::mode=truncate).
>>>>
>>>> Tested with included jtreg test through JPRT.
>>>>
>>>> Thanks,
>>>> Marcus
>>>>
>>>> On 01/14/2016 04:00 PM, Marcus Larsson wrote:
>>>>> Hi,
>>>>>
>>>>> Please review the following patch to make sure UL truncates 
>>>>> existing log files before writing to them. Since files are opened 
>>>>> in append mode, truncation isn't done automatically, so instead 
>>>>> the patch adds an attempt to remove the log file before opening it.
>>>>>
>>>>> Webrev:
>>>>> http://cr.openjdk.java.net/~mlarsson/8146879/webrev.00/
>>>>>
>>>>> Issue:
>>>>> https://bugs.openjdk.java.net/browse/JDK-8146879
>>>>>
>>>>> Testing:
>>>>> Included test through JPRT
>>>>>
>>>>> Thanks,
>>>>> Marcus
>>>>
>>>
>>
>