<html><head><style>body{font-family:Helvetica,Arial;font-size:13px}</style></head><body style="word-wrap:break-word;line-break:after-white-space"><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px;color:rgba(0,0,0,1.0);margin:0px;line-height:auto">Hi all,</div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px;color:rgba(0,0,0,1.0);margin:0px;line-height:auto"><br></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px;color:rgba(0,0,0,1.0);margin:0px;line-height:auto">I’ve been looking at the gc+heap=info output for post-9 JDKs:</div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px;color:rgba(0,0,0,1.0);margin:0px;line-height:auto"><br></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px;color:rgba(0,0,0,1.0);margin:0px;line-height:auto"><p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[16.607s][info][gc,heap ] GC(55) PSYoungGen: 1383840K->1600K(1612800K)</span></p><p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo">
</p><p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[16.607s][info][gc,heap ] GC(55) ParOldGen: 1348K->1348K(253952K)</span></p><div><span style="font-variant-ligatures:no-common-ligatures"><br></span></div></div>Unfortunately, there doesn’t seem to be a way to get the eden and survivor space occupancy at the info level. If we use gc+heap=debug we get the old PrintHeapAtGC output (twice per GC: once before and once after):<div><br></div><div><p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[4.194s][debug][gc,heap ] GC(11) Heap before GC invocations=12 (full 0): PSYoungGen total 1612800K, used 1383968K [0x000000008f800000, 0x0000000100000000, 0x0000000100000000)</span></p>
<p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[4.194s][debug][gc,heap ] GC(11) eden space 1382400K, 100% used [0x000000008f800000,0x00000000e3e00000,0x00000000e3e00000)</span></p>
<p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[4.194s][debug][gc,heap ] GC(11) from space 230400K, 0% used [0x00000000e3e00000,0x00000000e3f88000,0x00000000f1f00000)</span></p>
<p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[4.194s][debug][gc,heap ] GC(11) to space 230400K, 0% used [0x00000000f1f00000,0x00000000f1f00000,0x0000000100000000)</span></p>
<p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[4.194s][debug][gc,heap ] GC(11) ParOldGen total 253952K, used 1296K [0x0000000080000000, 0x000000008f800000, 0x000000008f800000)</span></p>
<p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[4.194s][debug][gc,heap ] GC(11) object space 253952K, 0% used [0x0000000080000000,0x00000000801440e0,0x000000008f800000)</span></p>
<p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[4.194s][debug][gc,heap ] GC(11) Metaspace used 7923K, capacity 8115K, committed 8320K, reserved 1056768K</span></p>
<p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[4.194s][debug][gc,heap ] GC(11) class space used 722K, capacity 790K, committed 896K, reserved 1048576K</span></p></div><div><span style="font-variant-ligatures:no-common-ligatures"><br></span></div><div>This contains the required information but it also increases the log size by 4x to 5x as it contains a lot of mostly useless and duplicated information.</div><div><br></div><div>I have a couple of changes (for ParNew and ParallelGC) to extend the gc+heap=info output with the occupancy info for eden and the survivors - the output looks like this:</div><div><br></div><div><p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[16.607s][info][gc,heap ] GC(55) PSYoungGen: 1383840K->1600K(1612800K) Eden: 1382400K->0K(1382400K) From: 1440K->1600K(230400K) To: 0K->0K(230400K)</span></p>
<p style="margin:0px;font-stretch:normal;font-size:11px;line-height:normal;font-family:Menlo"><span style="font-variant-ligatures:no-common-ligatures">[16.607s][info][gc,heap ] GC(55) ParOldGen: 1348K->1348K(253952K)</span></p></div><div><br></div><div>Is there interest in this? The changes are straightforward.</div><div><br></div><div>Tony</div><div><br></div><div><br><div id="bloop_sign_1555611177928604160" class="bloop_sign"><div><br></div><div><div>—————</div><div>Tony Printezis | @TonyPrintezis | <a href="mailto:tprintezis@twitter.com">tprintezis@twitter.com</a></div></div><div><br></div></div></div></body></html>