1 .TH IO.JS "1" "2010" "" ""
5 iojs \- Server-side JavaScript
33 Execute without arguments to start the REPL.
38 io.js is a set of libraries for javascript which allows
39 it to be used outside of the browser. It is primarily
40 focused on creating simple, easy to build network clients
46 -v, --version print iojs's version
48 -e, --eval script evaluate script
50 -p, --print print result of --eval
52 -i, --interactive always enter the REPL even if stdin
53 does not appear to be a terminal
55 -r, --require module to preload at startup
57 --no-deprecation silence deprecation warnings
59 --trace-deprecation show stack traces on deprecations
61 --throw-deprecation throw errors on deprecations
63 --v8-options print v8 command line options
65 --max-stack-size=val set max v8 stack size (bytes)
68 .SH ENVIRONMENT VARIABLES
71 \':\'\-separated list of directories prefixed to the module search path.
73 .IP NODE_MODULE_CONTEXTS
74 If set to 1 then modules will load in their own global contexts.
76 .IP NODE_DISABLE_COLORS
77 If set to 1 then colors will not be used in the REPL.
81 --use_strict (enforce strict mode)
82 type: bool default: false
83 --es_staging (enable all completed harmony features)
84 type: bool default: false
85 --harmony (enable all completed harmony features)
86 type: bool default: false
87 --harmony_shipping (enable all shipped harmony fetaures)
88 type: bool default: true
89 --harmony_modules (enable "harmony modules (implies block scoping)" (in progress))
90 type: bool default: false
91 --harmony_arrays (enable "harmony array methods" (in progress))
92 type: bool default: false
93 --harmony_array_includes (enable "harmony Array.prototype.includes" (in progress))
94 type: bool default: false
95 --harmony_regexps (enable "harmony regular expression extensions" (in progress))
96 type: bool default: false
97 --harmony_arrow_functions (enable "harmony arrow functions" (in progress))
98 type: bool default: false
99 --harmony_proxies (enable "harmony proxies" (in progress))
100 type: bool default: false
101 --harmony_sloppy (enable "harmony features in sloppy mode" (in progress))
102 type: bool default: false
103 --harmony_unicode (enable "harmony unicode escapes" (in progress))
104 type: bool default: false
105 --harmony_tostring (enable "harmony toString")
106 type: bool default: false
107 --harmony_numeric_literals (enable "harmony numeric literals")
108 type: bool default: true
109 --harmony_strings (enable "harmony string methods")
110 type: bool default: true
111 --harmony_scoping (enable "harmony block scoping")
112 type: bool default: true
113 --harmony_classes (enable "harmony classes (implies block scoping & object literal extension)")
114 type: bool default: true
115 --harmony_object_literals (enable "harmony object literal extensions")
116 type: bool default: true
117 --harmony_templates (enable "harmony template literals")
118 type: bool default: true
119 --compiled_keyed_generic_loads (use optimizing compiler to generate keyed generic load stubs)
120 type: bool default: false
121 --pretenuring_call_new (pretenure call new)
122 type: bool default: false
123 --allocation_site_pretenuring (pretenure with allocation sites)
124 type: bool default: true
125 --trace_pretenuring (trace pretenuring decisions of HAllocate instructions)
126 type: bool default: false
127 --trace_pretenuring_statistics (trace allocation site pretenuring statistics)
128 type: bool default: false
129 --track_fields (track fields with only smi values)
130 type: bool default: true
131 --track_double_fields (track fields with double values)
132 type: bool default: true
133 --track_heap_object_fields (track fields with heap values)
134 type: bool default: true
135 --track_computed_fields (track computed boilerplate fields)
136 type: bool default: true
137 --track_field_types (track field types)
138 type: bool default: true
139 --smi_binop (support smi representation in binary operations)
140 type: bool default: true
141 --vector_ics (support vector-based ics)
142 type: bool default: false
143 --optimize_for_size (Enables optimizations which favor memory size over execution speed.)
144 type: bool default: false
145 --unbox_double_arrays (automatically unbox arrays of doubles)
146 type: bool default: true
147 --string_slices (use string slices)
148 type: bool default: true
149 --crankshaft (use crankshaft)
150 type: bool default: true
151 --hydrogen_filter (optimization filter)
152 type: string default: *
153 --use_gvn (use hydrogen global value numbering)
154 type: bool default: true
155 --gvn_iterations (maximum number of GVN fix-point iterations)
157 --use_canonicalizing (use hydrogen instruction canonicalizing)
158 type: bool default: true
159 --use_inlining (use function inlining)
160 type: bool default: true
161 --use_escape_analysis (use hydrogen escape analysis)
162 type: bool default: true
163 --use_allocation_folding (use allocation folding)
164 type: bool default: true
165 --use_local_allocation_folding (only fold in basic blocks)
166 type: bool default: false
167 --use_write_barrier_elimination (eliminate write barriers targeting allocations in optimized code)
168 type: bool default: true
169 --max_inlining_levels (maximum number of inlining levels)
171 --max_inlined_source_size (maximum source size in bytes considered for a single inlining)
172 type: int default: 600
173 --max_inlined_nodes (maximum number of AST nodes considered for a single inlining)
174 type: int default: 196
175 --max_inlined_nodes_cumulative (maximum cumulative number of AST nodes considered for inlining)
176 type: int default: 400
177 --loop_invariant_code_motion (loop invariant code motion)
178 type: bool default: true
179 --fast_math (faster (but maybe less accurate) math functions)
180 type: bool default: true
181 --collect_megamorphic_maps_from_stub_cache (crankshaft harvests type feedback from stub cache)
182 type: bool default: true
183 --hydrogen_stats (print statistics for hydrogen)
184 type: bool default: false
185 --trace_check_elimination (trace check elimination phase)
186 type: bool default: false
187 --trace_hydrogen (trace generated hydrogen to file)
188 type: bool default: false
189 --trace_hydrogen_filter (hydrogen tracing filter)
190 type: string default: *
191 --trace_hydrogen_stubs (trace generated hydrogen for stubs)
192 type: bool default: false
193 --trace_hydrogen_file (trace hydrogen to given file name)
194 type: string default: NULL
195 --trace_phase (trace generated IR for specified phases)
196 type: string default: HLZ
197 --trace_inlining (trace inlining decisions)
198 type: bool default: false
199 --trace_load_elimination (trace load elimination)
200 type: bool default: false
201 --trace_store_elimination (trace store elimination)
202 type: bool default: false
203 --trace_alloc (trace register allocator)
204 type: bool default: false
205 --trace_all_uses (trace all use positions)
206 type: bool default: false
207 --trace_range (trace range analysis)
208 type: bool default: false
209 --trace_gvn (trace global value numbering)
210 type: bool default: false
211 --trace_representation (trace representation types)
212 type: bool default: false
213 --trace_removable_simulates (trace removable simulates)
214 type: bool default: false
215 --trace_escape_analysis (trace hydrogen escape analysis)
216 type: bool default: false
217 --trace_allocation_folding (trace allocation folding)
218 type: bool default: false
219 --trace_track_allocation_sites (trace the tracking of allocation sites)
220 type: bool default: false
221 --trace_migration (trace object migration)
222 type: bool default: false
223 --trace_generalization (trace map generalization)
224 type: bool default: false
225 --stress_pointer_maps (pointer map for every instruction)
226 type: bool default: false
227 --stress_environments (environment for every instruction)
228 type: bool default: false
229 --deopt_every_n_times (deoptimize every n times a deopt point is passed)
231 --deopt_every_n_garbage_collections (deoptimize every n garbage collections)
233 --print_deopt_stress (print number of possible deopt points)
234 type: bool default: false
235 --trap_on_deopt (put a break point before deoptimizing)
236 type: bool default: false
237 --trap_on_stub_deopt (put a break point before deoptimizing a stub)
238 type: bool default: false
239 --deoptimize_uncommon_cases (deoptimize uncommon cases)
240 type: bool default: true
241 --polymorphic_inlining (polymorphic inlining)
242 type: bool default: true
243 --use_osr (use on-stack replacement)
244 type: bool default: true
245 --array_bounds_checks_elimination (perform array bounds checks elimination)
246 type: bool default: true
247 --trace_bce (trace array bounds check elimination)
248 type: bool default: false
249 --array_bounds_checks_hoisting (perform array bounds checks hoisting)
250 type: bool default: false
251 --array_index_dehoisting (perform array index dehoisting)
252 type: bool default: true
253 --analyze_environment_liveness (analyze liveness of environment slots and zap dead values)
254 type: bool default: true
255 --load_elimination (use load elimination)
256 type: bool default: true
257 --check_elimination (use check elimination)
258 type: bool default: true
259 --store_elimination (use store elimination)
260 type: bool default: false
261 --dead_code_elimination (use dead code elimination)
262 type: bool default: true
263 --fold_constants (use constant folding)
264 type: bool default: true
265 --trace_dead_code_elimination (trace dead code elimination)
266 type: bool default: false
267 --unreachable_code_elimination (eliminate unreachable code)
268 type: bool default: true
269 --trace_osr (trace on-stack replacement)
270 type: bool default: false
271 --stress_runs (number of stress runs)
273 --lookup_sample_by_shared (when picking a function to optimize, watch for shared function info, not JSFunction itself)
274 type: bool default: true
275 --cache_optimized_code (cache optimized code for closures)
276 type: bool default: true
277 --flush_optimized_code_cache (flushes the cache of optimized code for closures on every GC)
278 type: bool default: true
279 --inline_construct (inline constructor calls)
280 type: bool default: true
281 --inline_arguments (inline functions with arguments object)
282 type: bool default: true
283 --inline_accessors (inline JavaScript accessors)
284 type: bool default: true
285 --escape_analysis_iterations (maximum number of escape analysis fix-point iterations)
287 --optimize_for_in (optimize functions containing for-in loops)
288 type: bool default: true
289 --concurrent_recompilation (optimizing hot functions asynchronously on a separate thread)
290 type: bool default: true
291 --job_based_recompilation (post tasks to v8::Platform instead of using a thread for concurrent recompilation)
292 type: bool default: false
293 --trace_concurrent_recompilation (track concurrent recompilation)
294 type: bool default: false
295 --concurrent_recompilation_queue_length (the length of the concurrent compilation queue)
297 --concurrent_recompilation_delay (artificial compilation delay in ms)
299 --block_concurrent_recompilation (block queued jobs until released)
300 type: bool default: false
301 --concurrent_osr (concurrent on-stack replacement)
302 type: bool default: true
303 --omit_map_checks_for_leaf_maps (do not emit check maps for constant values that have a leaf map, deoptimize the optimized code if the layout of the maps changes.)
304 type: bool default: true
305 --turbo_filter (optimization filter for TurboFan compiler)
306 type: string default: ~
307 --trace_turbo (trace generated TurboFan IR)
308 type: bool default: false
309 --trace_turbo_graph (trace generated TurboFan graphs)
310 type: bool default: false
311 --trace_turbo_cfg_file (trace turbo cfg graph (for C1 visualizer) to a given file name)
312 type: string default: NULL
313 --trace_turbo_types (trace TurboFan's types)
314 type: bool default: true
315 --trace_turbo_scheduler (trace TurboFan's scheduler)
316 type: bool default: false
317 --trace_turbo_reduction (trace TurboFan's various reducers)
318 type: bool default: false
319 --trace_turbo_jt (trace TurboFan's jump threading)
320 type: bool default: false
321 --turbo_asm (enable TurboFan for asm.js code)
322 type: bool default: true
323 --turbo_verify (verify TurboFan graphs at each phase)
324 type: bool default: false
325 --turbo_stats (print TurboFan statistics)
326 type: bool default: false
327 --turbo_types (use typed lowering in TurboFan)
328 type: bool default: true
329 --turbo_source_positions (track source code positions when building TurboFan IR)
330 type: bool default: false
331 --context_specialization (enable context specialization in TurboFan)
332 type: bool default: false
333 --turbo_deoptimization (enable deoptimization in TurboFan)
334 type: bool default: false
335 --turbo_inlining (enable inlining in TurboFan)
336 type: bool default: false
337 --turbo_inlining_intrinsics (enable inlining of intrinsics in TurboFan)
338 type: bool default: false
339 --trace_turbo_inlining (trace TurboFan inlining)
340 type: bool default: false
341 --loop_assignment_analysis (perform loop assignment analysis)
342 type: bool default: true
343 --turbo_profiling (enable profiling in TurboFan)
344 type: bool default: false
345 --turbo_reuse_spill_slots (reuse spill slots in TurboFan)
346 type: bool default: true
347 --turbo_delay_ssa_decon (delay ssa deconstruction in TurboFan register allocator)
348 type: bool default: false
349 --turbo_move_optimization (optimize gap moves in TurboFan)
350 type: bool default: true
351 --turbo_jt (enable jump threading)
352 type: bool default: true
353 --typed_array_max_size_in_heap (threshold for in-heap typed array)
354 type: int default: 64
355 --frame_count (number of stack frames inspected by the profiler)
357 --interrupt_budget (execution budget before interrupt is triggered)
358 type: int default: 6144
359 --type_info_threshold (percentage of ICs that must have type info to allow optimization)
360 type: int default: 25
361 --generic_ic_threshold (max percentage of megamorphic/generic ICs to allow optimization)
362 type: int default: 30
363 --self_opt_count (call count before self-optimization)
364 type: int default: 130
365 --trace_opt_verbose (extra verbose compilation tracing)
366 type: bool default: false
367 --debug_code (generate extra code (assertions) for debugging)
368 type: bool default: false
369 --code_comments (emit comments in code disassembly)
370 type: bool default: false
371 --enable_sse3 (enable use of SSE3 instructions if available)
372 type: bool default: true
373 --enable_sse4_1 (enable use of SSE4.1 instructions if available)
374 type: bool default: true
375 --enable_sahf (enable use of SAHF instruction if available (X64 only))
376 type: bool default: true
377 --enable_avx (enable use of AVX instructions if available)
378 type: bool default: true
379 --enable_fma3 (enable use of FMA3 instructions if available)
380 type: bool default: true
381 --enable_vfp3 (enable use of VFP3 instructions if available)
382 type: bool default: true
383 --enable_armv7 (enable use of ARMv7 instructions if available (ARM only))
384 type: bool default: true
385 --enable_armv8 (enable use of ARMv8 instructions if available (ARM 32-bit only))
386 type: bool default: true
387 --enable_neon (enable use of NEON instructions if available (ARM only))
388 type: bool default: true
389 --enable_sudiv (enable use of SDIV and UDIV instructions if available (ARM only))
390 type: bool default: true
391 --enable_mls (enable use of MLS instructions if available (ARM only))
392 type: bool default: true
393 --enable_movw_movt (enable loading 32-bit constant by means of movw/movt instruction pairs (ARM only))
394 type: bool default: false
395 --enable_unaligned_accesses (enable unaligned accesses for ARMv7 (ARM only))
396 type: bool default: true
397 --enable_32dregs (enable use of d16-d31 registers on ARM - this requires VFP3)
398 type: bool default: true
399 --enable_vldr_imm (enable use of constant pools for double immediate (ARM only))
400 type: bool default: false
401 --force_long_branches (force all emitted branches to be in long mode (MIPS only))
402 type: bool default: false
403 --expose_natives_as (expose natives in global object)
404 type: string default: NULL
405 --expose_debug_as (expose debug in global object)
406 type: string default: NULL
407 --expose_free_buffer (expose freeBuffer extension)
408 type: bool default: false
409 --expose_gc (expose gc extension)
410 type: bool default: false
411 --expose_gc_as (expose gc extension under the specified name)
412 type: string default: NULL
413 --expose_externalize_string (expose externalize string extension)
414 type: bool default: false
415 --expose_trigger_failure (expose trigger-failure extension)
416 type: bool default: false
417 --stack_trace_limit (number of stack frames to capture)
418 type: int default: 10
419 --builtins_in_stack_traces (show built-in functions in stack traces)
420 type: bool default: false
421 --disable_native_files (disable builtin natives files)
422 type: bool default: false
423 --inline_new (use fast inline allocation)
424 type: bool default: true
425 --trace_codegen (print name of functions for which code is generated)
426 type: bool default: false
427 --trace (trace function calls)
428 type: bool default: false
429 --mask_constants_with_cookie (use random jit cookie to mask large constants)
430 type: bool default: true
431 --lazy (use lazy compilation)
432 type: bool default: true
433 --trace_opt (trace lazy optimization)
434 type: bool default: false
435 --trace_opt_stats (trace lazy optimization statistics)
436 type: bool default: false
437 --opt (use adaptive optimizations)
438 type: bool default: true
439 --always_opt (always try to optimize functions)
440 type: bool default: false
441 --always_osr (always try to OSR functions)
442 type: bool default: false
443 --prepare_always_opt (prepare for turning on always opt)
444 type: bool default: false
445 --trace_deopt (trace optimize function deoptimization)
446 type: bool default: false
447 --trace_stub_failures (trace deoptimization of generated code stubs)
448 type: bool default: false
449 --serialize_toplevel (enable caching of toplevel scripts)
450 type: bool default: true
451 --serialize_inner (enable caching of inner functions)
452 type: bool default: false
453 --trace_serializer (print code serializer trace)
454 type: bool default: false
455 --min_preparse_length (minimum length for automatic enable preparsing)
456 type: int default: 1024
457 --max_opt_count (maximum number of optimization attempts before giving up.)
458 type: int default: 10
459 --compilation_cache (enable compilation cache)
460 type: bool default: true
461 --cache_prototype_transitions (cache prototype transitions)
462 type: bool default: true
463 --cpu_profiler_sampling_interval (CPU profiler sampling interval in microseconds)
464 type: int default: 1000
465 --trace_debug_json (trace debugging JSON request/response)
466 type: bool default: false
467 --trace_js_array_abuse (trace out-of-bounds accesses to JS arrays)
468 type: bool default: false
469 --trace_external_array_abuse (trace out-of-bounds-accesses to external arrays)
470 type: bool default: false
471 --trace_array_abuse (trace out-of-bounds accesses to all arrays)
472 type: bool default: false
473 --enable_liveedit (enable liveedit experimental feature)
474 type: bool default: true
475 --hard_abort (abort by crashing)
476 type: bool default: true
477 --stack_size (default size of stack region v8 is allowed to use (in kBytes))
478 type: int default: 984
479 --max_stack_trace_source_length (maximum length of function source code printed in a stack trace.)
480 type: int default: 300
481 --always_inline_smi_code (always inline smi code in non-opt code)
482 type: bool default: false
483 --min_semi_space_size (min size of a semi-space (in MBytes), the new space consists of twosemi-spaces)
485 --target_semi_space_size (target size of a semi-space (in MBytes) before triggering a GC)
487 --max_semi_space_size (max size of a semi-space (in MBytes), the new space consists of twosemi-spaces)
489 --semi_space_growth_factor (factor by which to grow the new space)
491 --experimental_new_space_growth_heuristic (Grow the new space based on the percentage of survivors instead of their absolute value.)
492 type: bool default: false
493 --max_old_space_size (max size of the old space (in Mbytes))
495 --initial_old_space_size (initial old space size (in Mbytes))
497 --max_executable_size (max size of executable memory (in Mbytes))
499 --gc_global (always perform global GCs)
500 type: bool default: false
501 --gc_interval (garbage collect after <n> allocations)
502 type: int default: -1
503 --trace_gc (print one trace line following each garbage collection)
504 type: bool default: false
505 --trace_gc_nvp (print one detailed trace line in name=value format after each garbage collection)
506 type: bool default: false
507 --trace_gc_ignore_scavenger (do not print trace line after scavenger collection)
508 type: bool default: false
509 --trace_idle_notification (print one trace line following each idle notification)
510 type: bool default: false
511 --trace_idle_notification_verbose (prints the heap state used by the idle notification)
512 type: bool default: false
513 --print_cumulative_gc_stat (print cumulative GC statistics in name=value format on exit)
514 type: bool default: false
515 --print_max_heap_committed (print statistics of the maximum memory committed for the heap in name=value format on exit)
516 type: bool default: false
517 --trace_gc_verbose (print more details following each garbage collection)
518 type: bool default: false
519 --trace_fragmentation (report fragmentation for old pointer and data pages)
520 type: bool default: false
521 --collect_maps (garbage collect maps from which no objects can be reached)
522 type: bool default: true
523 --weak_embedded_maps_in_optimized_code (make maps embedded in optimized code weak)
524 type: bool default: true
525 --weak_embedded_objects_in_optimized_code (make objects embedded in optimized code weak)
526 type: bool default: true
527 --flush_code (flush code that we expect not to use again (during full gc))
528 type: bool default: true
529 --flush_code_incrementally (flush code that we expect not to use again (incrementally))
530 type: bool default: true
531 --trace_code_flushing (trace code flushing progress)
532 type: bool default: false
533 --age_code (track un-executed functions to age code and flush only old code (required for code flushing))
534 type: bool default: true
535 --incremental_marking (use incremental marking)
536 type: bool default: true
537 --incremental_marking_steps (do incremental marking steps)
538 type: bool default: true
539 --concurrent_sweeping (use concurrent sweeping)
540 type: bool default: true
541 --trace_incremental_marking (trace progress of the incremental marking)
542 type: bool default: false
543 --track_gc_object_stats (track object counts and memory usage)
544 type: bool default: false
545 --heap_profiler_trace_objects (Dump heap object allocations/movements/size_updates)
546 type: bool default: false
547 --use_idle_notification (Use idle notification to reduce memory footprint.)
548 type: bool default: true
549 --use_ic (use inline caching)
550 type: bool default: true
551 --trace_ic (trace inline cache state transitions)
552 type: bool default: false
553 --native_code_counters (generate extra code for manipulating stats counters)
554 type: bool default: false
555 --always_compact (Perform compaction on every full GC)
556 type: bool default: false
557 --never_compact (Never perform compaction on full GC - testing only)
558 type: bool default: false
559 --compact_code_space (Compact code space on full non-incremental collections)
560 type: bool default: true
561 --incremental_code_compaction (Compact code space on full incremental collections)
562 type: bool default: true
563 --cleanup_code_caches_at_gc (Flush inline caches prior to mark compact collection and flush code caches in maps during mark compact cycle.)
564 type: bool default: true
565 --use_marking_progress_bar (Use a progress bar to scan large objects in increments when incremental marking is active.)
566 type: bool default: true
567 --zap_code_space (Zap free memory in code space with 0xCC while sweeping.)
568 type: bool default: true
569 --random_seed (Default seed for initializing random generator (0, the default, means to use system random).)
571 --trace_weak_arrays (trace WeakFixedArray usage)
572 type: bool default: false
573 --track_prototype_users (keep track of which maps refer to a given prototype object)
574 type: bool default: false
575 --use_verbose_printer (allows verbose printing)
576 type: bool default: true
577 --allow_natives_syntax (allow natives syntax)
578 type: bool default: false
579 --trace_parse (trace parsing and preparsing)
580 type: bool default: false
581 --trace_sim (Trace simulator execution)
582 type: bool default: false
583 --debug_sim (Enable debugging the simulator)
584 type: bool default: false
585 --check_icache (Check icache flushes in ARM and MIPS simulator)
586 type: bool default: false
587 --stop_sim_at (Simulator stop after x number of instructions)
589 --sim_stack_alignment (Stack alingment in bytes in simulator (4 or 8, 8 is default))
591 --sim_stack_size (Stack size of the ARM64 and MIPS64 simulator in kBytes (default is 2 MB))
592 type: int default: 2048
593 --log_regs_modified (When logging register values, only print modified registers.)
594 type: bool default: true
595 --log_colour (When logging, try to use coloured output.)
596 type: bool default: true
597 --ignore_asm_unimplemented_break (Don't break for ASM_UNIMPLEMENTED_BREAK macros.)
598 type: bool default: false
599 --trace_sim_messages (Trace simulator debug messages. Implied by --trace-sim.)
600 type: bool default: false
601 --stack_trace_on_illegal (print stack trace when an illegal exception is thrown)
602 type: bool default: false
603 --abort_on_uncaught_exception (abort program (dump core) when an uncaught exception is thrown)
604 type: bool default: false
605 --randomize_hashes (randomize hashes to avoid predictable hash collisions (with snapshots this option cannot override the baked-in seed))
606 type: bool default: true
607 --hash_seed (Fixed seed to use to hash property keys (0 means random)(with snapshots this option cannot override the baked-in seed))
609 --profile_deserialization (Print the time it takes to deserialize the snapshot.)
610 type: bool default: false
611 --regexp_optimization (generate optimized regexp code)
612 type: bool default: true
613 --testing_bool_flag (testing_bool_flag)
614 type: bool default: true
615 --testing_maybe_bool_flag (testing_maybe_bool_flag)
616 type: maybe_bool default: unset
617 --testing_int_flag (testing_int_flag)
618 type: int default: 13
619 --testing_float_flag (float-flag)
620 type: float default: 2.5
621 --testing_string_flag (string-flag)
622 type: string default: Hello, world!
623 --testing_prng_seed (Seed used for threading test randomness)
624 type: int default: 42
625 --testing_serialization_file (file in which to serialize heap)
626 type: string default: /tmp/serdes
627 --startup_blob (Write V8 startup blob file. (mksnapshot only))
628 type: string default: NULL
629 --profile_hydrogen_code_stub_compilation (Print the time it takes to lazily compile hydrogen code stubs.)
630 type: bool default: false
631 --predictable (enable predictable mode)
632 type: bool default: false
633 --help (Print usage message, including flags, on console)
634 type: bool default: true
635 --dump_counters (Dump counters on exit)
636 type: bool default: false
637 --debugger (Enable JavaScript debugger)
638 type: bool default: false
639 --map_counters (Map counters to a file)
640 type: string default:
641 --js_arguments (Pass all remaining arguments to the script. Alias for "--".)
642 type: arguments default:
643 --gdbjit (enable GDBJIT interface (disables compacting GC))
644 type: bool default: false
645 --gdbjit_full (enable GDBJIT interface for all code objects)
646 type: bool default: false
647 --gdbjit_dump (dump elf objects with debug info to disk)
648 type: bool default: false
649 --gdbjit_dump_filter (dump only objects containing this substring)
650 type: string default:
651 --force_marking_deque_overflows (force overflows of marking deque by reducing it's size to 64 words)
652 type: bool default: false
653 --stress_compaction (stress the GC compactor to flush out bugs (implies --force_marking_deque_overflows))
654 type: bool default: false
655 --log (Minimal logging (no API, code, GC, suspect, or handles samples).)
656 type: bool default: false
657 --log_all (Log all events to the log file.)
658 type: bool default: false
659 --log_api (Log API events to the log file.)
660 type: bool default: false
661 --log_code (Log code events to the log file without profiling.)
662 type: bool default: false
663 --log_gc (Log heap samples on garbage collection for the hp2ps tool.)
664 type: bool default: false
665 --log_handles (Log global handle events.)
666 type: bool default: false
667 --log_snapshot_positions (log positions of (de)serialized objects in the snapshot.)
668 type: bool default: false
669 --log_suspect (Log suspect operations.)
670 type: bool default: false
671 --prof (Log statistical profiling information (implies --log-code).)
672 type: bool default: false
673 --prof_browser_mode (Used with --prof, turns on browser-compatible mode for profiling.)
674 type: bool default: true
675 --log_regexp (Log regular expression execution.)
676 type: bool default: false
677 --logfile (Specify the name of the log file.)
678 type: string default: v8.log
679 --logfile_per_isolate (Separate log files for each isolate.)
680 type: bool default: true
681 --ll_prof (Enable low-level linux profiler.)
682 type: bool default: false
683 --perf_basic_prof (Enable perf linux profiler (basic support).)
684 type: bool default: false
685 --perf_jit_prof (Enable perf linux profiler (experimental annotate support).)
686 type: bool default: false
687 --gc_fake_mmap (Specify the name of the file for fake gc mmap used in ll_prof)
688 type: string default: /tmp/__v8_gc__
689 --log_internal_timer_events (Time internal events.)
690 type: bool default: false
691 --log_timer_events (Time events including external callbacks.)
692 type: bool default: false
693 --log_instruction_stats (Log AArch64 instruction statistics.)
694 type: bool default: false
695 --log_instruction_file (AArch64 instruction statistics log file.)
696 type: string default: arm64_inst.csv
697 --log_instruction_period (AArch64 instruction statistics logging period.)
698 type: int default: 4194304
699 --redirect_code_traces (output deopt information and disassembly into file code-<pid>-<isolate id>.asm)
700 type: bool default: false
701 --redirect_code_traces_to (output deopt information and disassembly into the given file)
702 type: string default: NULL
703 --hydrogen_track_positions (track source code positions when building IR)
704 type: bool default: false
705 --trace_elements_transitions (trace elements transitions)
706 type: bool default: false
707 --trace_creation_allocation_sites (trace the creation of allocation sites)
708 type: bool default: false
709 --print_code_stubs (print code stubs)
710 type: bool default: false
711 --test_secondary_stub_cache (test secondary stub cache by disabling the primary one)
712 type: bool default: false
713 --test_primary_stub_cache (test primary stub cache by disabling the secondary one)
714 type: bool default: false
715 --print_code (print generated code)
716 type: bool default: false
717 --print_opt_code (print optimized code)
718 type: bool default: false
719 --print_unopt_code (print unoptimized code before printing optimized code based on it)
720 type: bool default: false
721 --print_code_verbose (print more information for code)
722 type: bool default: false
723 --print_builtin_code (print generated code for builtins)
724 type: bool default: false
725 --sodium (print generated code output suitable for use with the Sodium code viewer)
726 type: bool default: false
727 --print_all_code (enable all flags related to printing code)
728 type: bool default: false
730 .SH RESOURCES AND DOCUMENTATION
732 See the website for documentation http://iojs.org/
734 Mailing list: http://groups.google.com/group/nodejs
736 IRC: irc.freenode.net #io.js