Re: Fwd: Request for review: 7173044: Memory monitor demo hangs if MemoryUsage obj returns -1 in getMax

[serguei.spit...@oracle.com]

The fix looks good.

Thanks,
Serguei

On 6/3/12 11:20 PM, David Holmes wrote:

On 4/06/2012 4:20 PM, Sean Chou wrote:

Thanks David. Do I need one more reviewer to support as it is a
modification to demo ?

I honestly don't know. It's a demo in serviceability area, so probably someone from serviceability should also give thumbs up.

David

On Mon, Jun 4, 2012 at 1:55 PM, David Holmes <david.hol...@oracle.com
<mailto:david.hol...@oracle.com>> wrote:

    Looks okay to me.

    David


    On 4/06/2012 3:55 PM, Sean Chou wrote:

        Hi David,

Thanks for your time, comments are added. The new webrev is

        http://cr.openjdk.java.net/~__zhouyx/7173044/webrev.02/
<http://cr.openjdk.java.net/~zhouyx/7173044/webrev.02/>  .
        Please have a look.

        On Mon, Jun 4, 2012 at 11:26 AM, David Holmes
<david.hol...@oracle.com <mailto:david.hol...@oracle.com>
<mailto:david.holmes@oracle.__com
<mailto:david.hol...@oracle.com>>> wrote:

            Hi Sean,

            This seems reasonable. Perhaps add a couple of comments:

            125  private float usedMemMax[]; // used when max pool size
        is undefined

202 if (totalMemory < 0) { // max is undefined for this pool

            David
            -----



            On 4/06/2012 12:12 PM, Sean Chou wrote:

                Hello,

                     Would any one like to take one more look ? It will
        help much !

                ---------- Forwarded message ----------
                From: *Sean Chou* <zho...@linux.vnet.ibm.com
<mailto:zho...@linux.vnet.ibm.com>
<mailto:zho...@linux.vnet.ibm.__com
<mailto:zho...@linux.vnet.ibm.com>>
<mailto:zho...@linux.vnet.ibm.
<mailto:zho...@linux.vnet.ibm.>____com
<mailto:zho...@linux.vnet.ibm.__com
<mailto:zho...@linux.vnet.ibm.com>>>>
                Date: Thu, May 31, 2012 at 3:17 PM
                Subject: Request for review: 7173044: Memory monitor
        demo hangs if
                MemoryUsage obj returns -1 in getMax
                To: serviceability-dev@openjdk.__j__ava.net
<http://java.net>
<mailto:serviceability-dev@__openjdk.java.net
<mailto:serviceability-dev@openjdk.java.net>>
<mailto:serviceability-dev@
<mailto:serviceability-dev@>__o__penjdk.java.net
<http://openjdk.java.net>

<mailto:serviceability-dev@__openjdk.java.net
<mailto:serviceability-dev@openjdk.java.net>>>


                Hi all,

                     MemoryMonitor demo will hang if MemoryUsage obj
        returns -1
                in getMax method.
                The demo obtains totalMemory from getMax method, and it
        is used in
                following loop:

        "    // .. Memory Free ..
                      big.setColor(mfColor);

int MemUsage = (int) (((totalMemory - usedMemory) /

                totalMemory) *
                10);
                      int i = 0;
                      for ( ; i < MemUsage ; i++) {

mfRect.setRect(x1+5,(float) y1+ssH+i*blockHeight,

                                     blockWidth, blockHeight-1);
                           big.fill(mfRect);
                      }
        "
                    If -1 is returned, MemUsage becomes a very large
        positive
                value and
                the loop hangs
                the demo.

The bug is not seen in current openjdk because the beans

                returned
                all has a Max
                value returned. However, -1 is allowed by spec when Max
        is not
                set for
                the bean, and
                other jdk might return.

                    In the patch, max is set to 1m or the max memory
        usage in
                history
                for the bean
                if there is no max specified. Please take a look.

                Bug:

http://bugs.sun.com/____bugdatabase/view_bug.do?bug_____id=7173044

<http://bugs.sun.com/__bugdatabase/view_bug.do?bug___id=7173044>
<http://bugs.sun.com/__bugdatabase/view_bug.do?bug___id=7173044
<http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7173044>>
                Webrev:
        http://cr.openjdk.java.net/~____zhouyx/7173044/webrev.01/
<http://cr.openjdk.java.net/~__zhouyx/7173044/webrev.01/>

<http://cr.openjdk.java.net/~__zhouyx/7173044/webrev.01/
<http://cr.openjdk.java.net/~zhouyx/7173044/webrev.01/>>  .


                --
                Best Regards,
                Sean Chou




                --
                Best Regards,
                Sean Chou




        --
        Best Regards,
        Sean Chou




--
Best Regards,
Sean Chou