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$ python3 tools/gc_log_report.py /tmp/ant.gc.log
logfile: /tmp/ant.gc.log
log rows: 602
major collections: 22
minor collections: 176
Collection Timing
major total count= 22 avg= 21.57ms p50= 28.90ms p95= 36.31ms max= 65.49ms
major objects count= 22 avg= 20.23ms p50= 27.32ms p95= 34.71ms max= 61.83ms
minor total count= 176 avg= 1.34ms p50= 985.00us p95= 3.10ms max= 13.45ms
minor objects count= 176 avg= 960.43us p50= 592.00us p95= 2.62ms max= 12.43ms
Latest Memory
rss 1.0GiB
external 400.4MiB
live objects 254210
old objects 254210
young objects 0
pool alloc 517.5KiB
High Water Marks
max rss 1.1GiB
max external 400.9MiB
max live 345224
max remset 183
max active_async 2
max next_ticks 7
max microtasks 17
max pending_rejections 6
Recent Major Timeline
26.26ms ###########................. live=254210 rss= 1.0GiB
31.99ms ##############.............. live=254210 rss= 1.0GiB
33.50ms ##############.............. live=254210 rss= 1.0GiB
36.41ms ################............ live=254210 rss= 1.0GiB
33.63ms ##############.............. live=254210 rss= 1.0GiB
65.49ms ############################ live=254210 rss= 1.0GiB
33.60ms ##############.............. live=254210 rss= 1.0GiB
31.54ms #############............... live=254210 rss= 1.0GiB
34.46ms ###############............. live=254210 rss= 1.0GiB
33.26ms ##############.............. live=254210 rss= 1.0GiB
34.46ms ###############............. live=254210 rss= 1.0GiB
32.94ms ##############.............. live=254210 rss= 1.0GiB
Recent Minor Timeline
463.00us #........................... young_before=4096 survivors=4096
479.00us #........................... young_before=4096 survivors=4096
495.00us #........................... young_before=4096 survivors=4096
476.00us #........................... young_before=4099 survivors=2708
579.00us #........................... young_before=4100 survivors=2049
502.00us #........................... young_before=4617 survivors=1818
529.00us #........................... young_before=4097 survivors=919
929.00us ##.......................... young_before=4109 survivors=709
601.00us #........................... young_before=4096 survivors=3101
509.00us #........................... young_before=4096 survivors=4096
479.00us #........................... young_before=4096 survivors=4096
835.00us ##.......................... young_before=4096 survivors=4096
Major Object GC Hotspots
roots_ns 348.00ms 79.0% ############################
sweep_ns 78.98ms 17.9% ######......................
trim_ns 2.72ms 0.6% ............................
shape_ns 6.23ms 1.4% #...........................
closure_ns 3.90ms 0.9% ............................
upvalue_ns 579.00us 0.1% ............................
Major Root Source Breakdown
vm_roots_ns 311.11ms 89.4% ############################
coroutine_roots_ns 35.17ms 10.1% ###.........................
runtime_roots_ns 145.00us 0.0% ............................
module_roots_ns 2.00us 0.0% ............................
rejection_roots_ns 0ns 0.0% ............................
cfunc_roots_ns 1.00us 0.0% ............................
registered_roots_ns 92.00us 0.0% ............................
subsystem_roots_ns 754.00us 0.2% ............................
pending_promise_roots_ns 5.00us 0.0% ............................
native_stack_roots_ns 242.00us 0.1% ............................
permanent_roots_ns 477.00us 0.1% ............................
Major VM Root Breakdown
vm_stack_values_ns 337.07ms 97.5% ############################
vm_frame_funcs_ns 8.21ms 2.4% #...........................
vm_frame_meta_ns 73.00us 0.0% ............................
vm_open_upvalues_ns 481.00us 0.1% ............................
vm_frame_upvalues_ns 20.00us 0.0% ............................
Major Main VM Breakdown
main_vm_stack_values_ns 302.41ms 97.2% ############################
main_vm_frame_funcs_ns 8.19ms 2.6% #...........................
main_vm_frame_meta_ns 26.00us 0.0% ............................
main_vm_open_upvalues_ns 465.00us 0.1% ............................
main_vm_frame_upvalues_ns 7.00us 0.0% ............................
Major Main VM Stack Occupancy
scanned slots 208052
non-undef slots 127327 61.2% ############################
markable slots 111811 53.7% #########################...
trimmed slots 0 0.0% ............................
Major Main VM Frame Meta Population
frames scanned 194
callee set 179 92.3% ##########################..
this set 194 100.0% ############################
new_target set 26 13.4% ####........................
super_val set 101 52.1% ###############.............
with_obj set 24 12.4% ###.........................
completion active 0 0.0% ............................
Major Main VM Frame Meta Timing
callee 14.00us 53.8% ############################
this 6.00us 23.1% ############................
new_target 4.00us 15.4% ########....................
super_val 2.00us 7.7% ####........................
with_obj 0ns 0.0% ............................
completion 0ns 0.0% ............................
Major Main VM Frame Meta New Marks
total new marks 56
callee 56 100.0% ############################
this 0 0.0% ............................
new_target 0 0.0% ............................
super_val 0 0.0% ............................
with_obj 0 0.0% ............................
completion 0 0.0% ............................
Major Main Callee New Mark Types
total new marks 56
heap objects 29 51.8% ############################
closures 27 48.2% ##########################..
functions 0 0.0% ............................
Major Coroutine Root Breakdown
coroutine_vm_ns 34.82ms 99.1% ############################
coroutine_fields_ns 319.00us 0.9% ............................
coroutine_args_ns 5.00us 0.0% ............................
Major Coroutine VM Breakdown
coroutine_vm_stack_values_ns 34.66ms 99.7% ############################
coroutine_vm_frame_funcs_ns 22.00us 0.1% ............................
coroutine_vm_frame_meta_ns 47.00us 0.1% ............................
coroutine_vm_open_upvalues_ns 16.00us 0.0% ............................
coroutine_vm_frame_upvalues_ns 13.00us 0.0% ............................
Major Coroutine VM Stack Occupancy
scanned slots 2222
non-undef slots 1617 72.8% ############################
markable slots 1016 45.7% ##################..........
trimmed slots 0 0.0% ............................
Major Coroutine Frame Meta Population
frames scanned 526
callee set 526 100.0% ############################
this set 526 100.0% ############################
new_target set 260 49.4% ##############..............
super_val set 362 68.8% ###################.........
with_obj set 262 49.8% ##############..............
completion active 0 0.0% ............................
Major Coroutine Frame Meta Timing
callee 33.00us 70.2% ############################
this 2.00us 4.3% ##..........................
new_target 5.00us 10.6% ####........................
super_val 1.00us 2.1% #...........................
with_obj 2.00us 4.3% ##..........................
completion 4.00us 8.5% ###.........................
Major Coroutine Frame Meta New Marks
total new marks 65
callee 59 90.8% ############################
this 6 9.2% ###.........................
new_target 0 0.0% ............................
super_val 0 0.0% ............................
with_obj 0 0.0% ............................
completion 0 0.0% ............................
Major Coroutine Callee Frame Split
frames scanned 526
top frames 260 49.4% ##############..............
non-top frames 266 50.6% ##############..............
callee set 526 100.0% ############################
top callee set 260 49.4% ##############..............
non-top callee set 266 50.6% ##############..............
Major Coroutine Callee Frame Timing
top frame 28.00us 84.8% ############################
non-top frames 5.00us 15.2% #####.......................
Major Coroutine Callee Frame New Marks
total new marks 59
top frame 59 100.0% ############################
non-top frames 0 0.0% ............................
Major Coroutine Top-Frame Callee New Mark Types
total new marks 59
heap objects 35 59.3% ############################
closures 24 40.7% ###################.........
functions 0 0.0% ............................
Major Coroutine Callee New Mark Types
total new marks 59
heap objects 35 59.3% ############################
closures 24 40.7% ###################.........
functions 0 0.0% ............................
Minor Object GC Hotspots
remember_ns 2.78ms 1.7% #...........................
roots_ns 134.18ms 84.0% ############################
sweep_ns 21.03ms 13.2% ####........................
promote_ns 1.75ms 1.1% ............................
Minor Root Source Breakdown
vm_roots_ns 108.50ms 80.9% ############################
coroutine_roots_ns 20.85ms 15.5% #####.......................
runtime_roots_ns 20.00us 0.0% ............................
module_roots_ns 6.00us 0.0% ............................
rejection_roots_ns 3.00us 0.0% ............................
cfunc_roots_ns 2.00us 0.0% ............................
registered_roots_ns 130.00us 0.1% ............................
subsystem_roots_ns 3.11ms 2.3% #...........................
pending_promise_roots_ns 122.00us 0.1% ............................
native_stack_roots_ns 1.39ms 1.0% ............................
permanent_roots_ns 0ns 0.0% ............................
Minor VM Root Breakdown
vm_stack_values_ns 90.05ms 70.6% ############################
vm_frame_funcs_ns 17.25ms 13.5% #####.......................
vm_frame_meta_ns 17.74ms 13.9% ######......................
vm_open_upvalues_ns 2.36ms 1.9% #...........................
vm_frame_upvalues_ns 137.00us 0.1% ............................
Minor Main VM Stack Occupancy
scanned slots 1044326
non-undef slots 952046 91.2% ############################
markable slots 847486 81.2% #########################...
trimmed slots 0 0.0% ............................
Minor Main VM Breakdown
main_vm_stack_values_ns 89.23ms 82.3% ############################
main_vm_frame_funcs_ns 16.94ms 15.6% #####.......................
main_vm_frame_meta_ns 91.00us 0.1% ............................
main_vm_open_upvalues_ns 2.16ms 2.0% #...........................
main_vm_frame_upvalues_ns 23.00us 0.0% ............................
Minor Main VM Frame Meta Population
frames scanned 2256
callee set 2182 96.7% ###########################.
this set 2256 100.0% ############################
new_target set 185 8.2% ##..........................
super_val set 1531 67.9% ###################.........
with_obj set 177 7.8% ##..........................
completion active 0 0.0% ............................
Minor Main VM Frame Meta Timing
callee 47.00us 51.6% ############################
this 10.00us 11.0% ######......................
new_target 9.00us 9.9% #####.......................
super_val 11.00us 12.1% #######.....................
with_obj 4.00us 4.4% ##..........................
completion 10.00us 11.0% ######......................
Minor Main VM Frame Meta New Marks
total new marks 344
callee 343 99.7% ############################
this 1 0.3% ............................
new_target 0 0.0% ............................
super_val 0 0.0% ............................
with_obj 0 0.0% ............................
completion 0 0.0% ............................
Minor Main Callee New Mark Types
total new marks 343
heap objects 37 10.8% ###.........................
closures 306 89.2% ############################
functions 0 0.0% ............................
Minor Coroutine Root Breakdown
coroutine_vm_ns 20.29ms 98.5% ############################
coroutine_fields_ns 234.00us 1.1% ............................
coroutine_args_ns 69.00us 0.3% ............................
Minor Coroutine VM Breakdown
coroutine_vm_stack_values_ns 814.00us 4.3% #...........................
coroutine_vm_frame_funcs_ns 311.00us 1.6% ............................
coroutine_vm_frame_meta_ns 17.64ms 92.4% ############################
coroutine_vm_open_upvalues_ns 207.00us 1.1% ............................
coroutine_vm_frame_upvalues_ns 114.00us 0.6% ............................
Minor Coroutine VM Stack Occupancy
scanned slots 35496
non-undef slots 25600 72.1% ############################
markable slots 16421 46.3% ##################..........
trimmed slots 0 0.0% ............................
Minor Coroutine Frame Meta Population
frames scanned 8640
callee set 8640 100.0% ############################
this set 8640 100.0% ############################
new_target set 4288 49.6% ##############..............
super_val set 6000 69.4% ###################.........
with_obj set 4310 49.9% ##############..............
completion active 0 0.0% ............................
Minor Coroutine Frame Meta Timing
callee 17.31ms 98.1% ############################
this 72.00us 0.4% ............................
new_target 68.00us 0.4% ............................
super_val 71.00us 0.4% ............................
with_obj 62.00us 0.4% ............................
completion 60.00us 0.3% ............................
Minor Coroutine Frame Meta New Marks
total new marks 581883
callee 581881 100.0% ############################
this 2 0.0% ............................
new_target 0 0.0% ............................
super_val 0 0.0% ............................
with_obj 0 0.0% ............................
completion 0 0.0% ............................
Minor Coroutine Callee Frame Split
frames scanned 8640
top frames 4286 49.6% ##############..............
non-top frames 4354 50.4% ##############..............
callee set 8640 100.0% ############################
top callee set 4286 49.6% ##############..............
non-top callee set 4354 50.4% ##############..............
Minor Coroutine Callee Frame Timing
top frame 17.25ms 99.6% ############################
non-top frames 67.00us 0.4% ............................
Minor Coroutine Callee Frame New Marks
total new marks 581881
top frame 581878 100.0% ############################
non-top frames 3 0.0% ............................
Minor Coroutine Top-Frame Callee New Mark Types
total new marks 581878
heap objects 15 0.0% ............................
closures 176445 30.3% ############................
functions 405418 69.7% ############################
Minor Coroutine Non-Top Callee New Mark Types
total new marks 3
heap objects 0 0.0% ............................
closures 2 66.7% ############################
functions 1 33.3% ##############..............
Minor Coroutine Callee New Mark Types
total new marks 581881
heap objects 15 0.0% ............................
closures 176447 30.3% ############................
functions 405419 69.7% ############################
$ python3 tools/gc_log_report.py /tmp/ant.gc.log
logfile: /tmp/ant.gc.log
log rows: 3802
major collections: 166
minor collections: 1095
Collection Timing
major total count= 166 avg= 33.86ms p50= 35.60ms p95= 37.55ms max= 55.85ms
major objects count= 166 avg= 32.40ms p50= 34.11ms p95= 36.01ms max= 53.11ms
minor total count=1095 avg= 739.05us p50= 573.00us p95= 1.40ms max= 10.38ms
minor objects count=1095 avg= 429.97us p50= 281.00us p95= 967.50us max= 9.34ms
Latest Memory
rss 1.1GiB
external 400.4MiB
live objects 269578
old objects 269578
young objects 0
pool alloc 762.9KiB
High Water Marks
max rss 1.1GiB
max external 400.9MiB
max live 345689
max remset 355
max active_async 2
max next_ticks 7
max microtasks 17
max pending_rejections 4
Recent Major Timeline
35.21ms ##################.......... live=269578 rss= 1.1GiB
37.23ms ###################......... live=269578 rss= 1.1GiB
36.38ms ##################.......... live=269578 rss= 1.1GiB
36.09ms ##################.......... live=269578 rss= 1.1GiB
36.29ms ##################.......... live=269578 rss= 1.1GiB
35.46ms ##################.......... live=269578 rss= 1.1GiB
35.52ms ##################.......... live=269578 rss= 1.1GiB
36.02ms ##################.......... live=269578 rss= 1.1GiB
35.48ms ##################.......... live=269578 rss= 1.1GiB
36.80ms ##################.......... live=269578 rss= 1.1GiB
35.34ms ##################.......... live=269578 rss= 1.1GiB
35.31ms ##################.......... live=269578 rss= 1.1GiB
Recent Minor Timeline
533.00us #........................... young_before=4097 survivors=2454
596.00us ##.......................... young_before=4097 survivors=921
823.00us ##.......................... young_before=4097 survivors=2999
791.00us ##.......................... young_before=4096 survivors=4096
566.00us ##.......................... young_before=4096 survivors=4096
525.00us #........................... young_before=4096 survivors=4096
513.00us #........................... young_before=4096 survivors=4096
504.00us #........................... young_before=4100 survivors=3527
821.00us ##.......................... young_before=4097 survivors=2135
577.00us ##.......................... young_before=4097 survivors=2151
559.00us ##.......................... young_before=4101 survivors=2840
550.00us #........................... young_before=4361 survivors=977
Major Object GC Hotspots
roots_ns 4.12s 76.7% ############################
sweep_ns 1.18s 21.9% ########....................
trim_ns 1.43ms 0.0% ............................
shape_ns 25.28ms 0.5% ............................
closure_ns 43.56ms 0.8% ............................
upvalue_ns 7.60ms 0.1% ............................
Major Root Source Breakdown
vm_roots_ns 4.07s 98.8% ############################
coroutine_roots_ns 27.42ms 0.7% ............................
runtime_roots_ns 187.00us 0.0% ............................
module_roots_ns 6.00us 0.0% ............................
rejection_roots_ns 0ns 0.0% ............................
cfunc_roots_ns 3.00us 0.0% ............................
registered_roots_ns 1.27ms 0.0% ............................
subsystem_roots_ns 10.98ms 0.3% ............................
pending_promise_roots_ns 42.00us 0.0% ............................
native_stack_roots_ns 2.92ms 0.1% ............................
permanent_roots_ns 5.12ms 0.1% ............................
Major VM Root Breakdown
vm_stack_values_ns 4.09s 99.7% ############################
vm_frame_funcs_ns 5.78ms 0.1% ............................
vm_frame_meta_ns 4.87ms 0.1% ............................
vm_open_upvalues_ns 636.00us 0.0% ............................
vm_frame_upvalues_ns 246.00us 0.0% ............................
Major Coroutine Root Breakdown
coroutine_vm_ns 25.46ms 93.4% ############################
coroutine_fields_ns 1.74ms 6.4% ##..........................
coroutine_args_ns 50.00us 0.2% ............................
Minor Object GC Hotspots
remember_ns 15.25ms 3.3% #...........................
roots_ns 344.06ms 74.4% ############################
sweep_ns 80.20ms 17.3% #######.....................
promote_ns 22.85ms 4.9% ##..........................
Minor Root Source Breakdown
vm_roots_ns 159.88ms 46.5% ############################
coroutine_roots_ns 137.36ms 40.0% ########################....
runtime_roots_ns 52.00us 0.0% ............................
module_roots_ns 24.00us 0.0% ............................
rejection_roots_ns 22.00us 0.0% ............................
cfunc_roots_ns 18.00us 0.0% ............................
registered_roots_ns 595.00us 0.2% ............................
subsystem_roots_ns 35.22ms 10.2% ######......................
pending_promise_roots_ns 459.00us 0.1% ............................
native_stack_roots_ns 10.19ms 3.0% ##..........................
permanent_roots_ns 0ns 0.0% ............................
Minor VM Root Breakdown
vm_stack_values_ns 145.97ms 49.9% ############################
vm_frame_funcs_ns 17.19ms 5.9% ###.........................
vm_frame_meta_ns 125.28ms 42.8% ########################....
vm_open_upvalues_ns 3.23ms 1.1% #...........................
vm_frame_upvalues_ns 830.00us 0.3% ............................
Minor Coroutine Root Breakdown
coroutine_vm_ns 134.96ms 99.1% ############################
coroutine_fields_ns 858.00us 0.6% ............................
coroutine_args_ns 390.00us 0.3% ............................
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