RFR: Traversal should resize TLABs

[Roman Kennke]

Very good catch! Thank you!

Roman


Am 18. Juli 2018 19:54:44 MESZ schrieb Aleksey Shipilev <shade at redhat.com>:
>http://cr.openjdk.java.net/~shade/shenandoah/traversal-tlabs/webrev.01/
>
>Traversal massively wastes allocated memory in TLABs, because it does
>not hook up to resizing
>machinery. Up to 20% of allocations go wasteful, see the data below.
>Fix is simple, except that we
>need to reach CollectedHeap protected methods from ShTraversalGC, which
>requires us to have adapters
>in ShHeap. Actually, the whole thing should be done in some kind of "GC
>prolog", let's keep it for
>future cleanups.
>
>Testing: tier3_gc_shenandoah (in progress), specjbb with TLAB tracing
>
>Thanks,
>-Aleksey
>
>------ 8<
>---------------------------------------------------------------------------
>
># adaptive
>[5.946s][info][gc     ]   GC(0)   5652479K alloc,  3893787K ( 68.9%)
>waste, <total>
>[43.601s][info][gc     ]  GC(1)  71553526K alloc,  9370547K ( 13.1%)
>waste, <total>
>[59.725s][info][gc     ]  GC(2)  66180095K alloc, 10988559K ( 16.6%)
>waste, <total>
>[77.877s][info][gc     ]  GC(3)  66068479K alloc,  5222993K (  7.9%)
>waste, <total>
>[97.925s][info][gc     ]  GC(4)  71254015K alloc,  4062446K (  5.7%)
>waste, <total>
>[117.137s][info][gc     ] GC(5)  71286783K alloc,  2857408K (  4.0%)
>waste, <total>
>[137.900s][info][gc     ] GC(6)  71288831K alloc,  2253194K (  3.2%)
>waste, <total>
>[154.789s][info][gc     ] GC(7)  68042044K alloc,  1875467K (  2.8%)
>waste, <total>
>[173.882s][info][gc     ] GC(8)  70169599K alloc,  1659220K (  2.4%)
>waste, <total>
>[193.410s][info][gc     ] GC(9)  70141951K alloc,  1383108K (  2.0%)
>waste, <total>
>[212.966s][info][gc     ] GC(10) 70141931K alloc,  1378965K (  2.0%)
>waste, <total>
>[232.226s][info][gc     ] GC(11) 70154857K alloc,  1282440K (  1.8%)
>waste, <total>
>[252.349s][info][gc     ] GC(12) 72239005K alloc,  1105413K (  1.5%)
>waste, <total>
>[272.450s][info][gc     ] GC(13) 72202913K alloc,  1057945K (  1.5%)
>waste, <total>
>[292.663s][info][gc     ] GC(14) 72290175K alloc,  1151170K (  1.6%)
>waste, <total>
>
># traversal (baseline)
>[6.053s][info][gc     ]   GC(0)   5554175K alloc,  3797414K ( 68.4%)
>waste, <total>
>[43.459s][info][gc     ]  GC(1)  71348223K alloc,  9385812K ( 13.2%)
>waste, <total>
>[59.773s][info][gc     ]  GC(2)  71843839K alloc, 16682101K ( 23.2%)
>waste, <total>
>[77.294s][info][gc     ]  GC(3)  70929407K alloc, 16762337K ( 23.6%)
>waste, <total>
>[95.809s][info][gc     ]  GC(4)  75781100K alloc, 16558988K ( 21.9%)
>waste, <total>
>[112.460s][info][gc     ] GC(5)  75388405K alloc, 16367333K ( 21.7%)
>waste, <total>
>[126.806s][info][gc     ] GC(6)  75452415K alloc, 15717772K ( 20.8%)
>waste, <total>
>[142.914s][info][gc     ] GC(7)  75321343K alloc, 16012333K ( 21.3%)
>waste, <total>
>[160.921s][info][gc     ] GC(8)  80233471K alloc, 16553359K ( 20.6%)
>waste, <total>
>[179.152s][info][gc     ] GC(9)  80009194K alloc, 16397760K ( 20.5%)
>waste, <total>
>[196.942s][info][gc     ] GC(10) 79896575K alloc, 16592765K ( 20.8%)
>waste, <total>
>[214.997s][info][gc     ] GC(11) 79801343K alloc, 15969714K ( 20.0%)
>waste, <total>
>[234.534s][info][gc     ] GC(12) 84979692K alloc, 16523232K ( 19.4%)
>waste, <total>
>[251.063s][info][gc     ] GC(14) 74365951K alloc, 15874486K ( 21.3%)
>waste, <total>
>[267.591s][info][gc     ] GC(15) 74340332K alloc, 16450176K ( 22.1%)
>waste, <total>
>[284.073s][info][gc     ] GC(16) 74270197K alloc, 16100433K ( 21.7%)
>waste, <total>
>[300.440s][info][gc     ] GC(17) 73779199K alloc, 16653813K ( 22.6%)
>waste, <total>
>
># traversal (fixed)
>[6.001s][info][gc     ]   GC(0)   5614951K alloc,  3862725K ( 68.8%)
>waste, <total>
>[44.277s][info][gc     ]  GC(1)  71520255K alloc,  9494430K ( 13.3%)
>waste, <total>
>[62.675s][info][gc     ]  GC(2)  71809023K alloc,  8801335K ( 12.3%)
>waste, <total>
>[81.899s][info][gc     ]  GC(3)  70963199K alloc,  4409301K (  6.2%)
>waste, <total>
>[102.628s][info][gc     ] GC(4)  75913783K alloc,  3310107K (  4.4%)
>waste, <total>
>[123.468s][info][gc     ] GC(5)  75509807K alloc,  2469812K (  3.3%)
>waste, <total>
>[144.511s][info][gc     ] GC(6)  75313089K alloc,  1738572K (  2.3%)
>waste, <total>
>[165.515s][info][gc     ] GC(7)  75143596K alloc,  1404853K (  1.9%)
>waste, <total>
>[187.935s][info][gc     ] GC(8)  80227327K alloc,  1227961K (  1.5%)
>waste, <total>
>[210.558s][info][gc     ] GC(9)  80091135K alloc,  1006566K (  1.3%)
>waste, <total>
>[234.604s][info][gc     ] GC(10) 80057234K alloc,   950299K (  1.2%)
>waste, <total>
>[256.416s][info][gc     ] GC(11) 80006606K alloc,   871344K (  1.1%)
>waste, <total>
>[279.285s][info][gc     ] GC(12) 85073731K alloc,   792366K (  0.9%)
>waste, <total>
>[303.241s][info][gc     ] GC(13) 84984293K alloc,   790728K (  0.9%)
>waste, <total>

-- 
Diese Nachricht wurde von meinem Android-Gerät mit K-9 Mail gesendet.