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
66 .SH ENVIRONMENT VARIABLES
69 \':\'\-separated list of directories prefixed to the module search path.
71 .IP NODE_DISABLE_COLORS
72 If set to 1 then colors will not be used in the REPL.
76 --use_strict (enforce strict mode)
77 type: bool default: false
78 --es_staging (enable all completed harmony features)
79 type: bool default: false
80 --harmony (enable all completed harmony features)
81 type: bool default: false
82 --harmony_shipping (enable all shipped harmony features)
83 type: bool default: true
84 --harmony_modules (enable "harmony modules (implies block scoping)" (in progress))
85 type: bool default: false
86 --harmony_arrays (enable "harmony array methods" (in progress))
87 type: bool default: false
88 --harmony_array_includes (enable "harmony Array.prototype.includes" (in progress))
89 type: bool default: false
90 --harmony_regexps (enable "harmony regular expression extensions" (in progress))
91 type: bool default: false
92 --harmony_arrow_functions (enable "harmony arrow functions" (in progress))
93 type: bool default: false
94 --harmony_proxies (enable "harmony proxies" (in progress))
95 type: bool default: false
96 --harmony_sloppy (enable "harmony features in sloppy mode" (in progress))
97 type: bool default: false
98 --harmony_unicode (enable "harmony unicode escapes" (in progress))
99 type: bool default: false
100 --harmony_tostring (enable "harmony toString")
101 type: bool default: false
102 --harmony_numeric_literals (enable "harmony numeric literals")
103 type: bool default: true
104 --harmony_strings (enable "harmony string methods")
105 type: bool default: true
106 --harmony_scoping (enable "harmony block scoping")
107 type: bool default: true
108 --harmony_classes (enable "harmony classes (implies block scoping & object literal extension)")
109 type: bool default: true
110 --harmony_object_literals (enable "harmony object literal extensions")
111 type: bool default: true
112 --harmony_templates (enable "harmony template literals")
113 type: bool default: true
114 --compiled_keyed_generic_loads (use optimizing compiler to generate keyed generic load stubs)
115 type: bool default: false
116 --pretenuring_call_new (pretenure call new)
117 type: bool default: false
118 --allocation_site_pretenuring (pretenure with allocation sites)
119 type: bool default: true
120 --trace_pretenuring (trace pretenuring decisions of HAllocate instructions)
121 type: bool default: false
122 --trace_pretenuring_statistics (trace allocation site pretenuring statistics)
123 type: bool default: false
124 --track_fields (track fields with only smi values)
125 type: bool default: true
126 --track_double_fields (track fields with double values)
127 type: bool default: true
128 --track_heap_object_fields (track fields with heap values)
129 type: bool default: true
130 --track_computed_fields (track computed boilerplate fields)
131 type: bool default: true
132 --track_field_types (track field types)
133 type: bool default: true
134 --smi_binop (support smi representation in binary operations)
135 type: bool default: true
136 --vector_ics (support vector-based ics)
137 type: bool default: false
138 --optimize_for_size (Enables optimizations which favor memory size over execution speed.)
139 type: bool default: false
140 --unbox_double_arrays (automatically unbox arrays of doubles)
141 type: bool default: true
142 --string_slices (use string slices)
143 type: bool default: true
144 --crankshaft (use crankshaft)
145 type: bool default: true
146 --hydrogen_filter (optimization filter)
147 type: string default: *
148 --use_gvn (use hydrogen global value numbering)
149 type: bool default: true
150 --gvn_iterations (maximum number of GVN fix-point iterations)
152 --use_canonicalizing (use hydrogen instruction canonicalizing)
153 type: bool default: true
154 --use_inlining (use function inlining)
155 type: bool default: true
156 --use_escape_analysis (use hydrogen escape analysis)
157 type: bool default: true
158 --use_allocation_folding (use allocation folding)
159 type: bool default: true
160 --use_local_allocation_folding (only fold in basic blocks)
161 type: bool default: false
162 --use_write_barrier_elimination (eliminate write barriers targeting allocations in optimized code)
163 type: bool default: true
164 --max_inlining_levels (maximum number of inlining levels)
166 --max_inlined_source_size (maximum source size in bytes considered for a single inlining)
167 type: int default: 600
168 --max_inlined_nodes (maximum number of AST nodes considered for a single inlining)
169 type: int default: 196
170 --max_inlined_nodes_cumulative (maximum cumulative number of AST nodes considered for inlining)
171 type: int default: 400
172 --loop_invariant_code_motion (loop invariant code motion)
173 type: bool default: true
174 --fast_math (faster (but maybe less accurate) math functions)
175 type: bool default: true
176 --collect_megamorphic_maps_from_stub_cache (crankshaft harvests type feedback from stub cache)
177 type: bool default: true
178 --hydrogen_stats (print statistics for hydrogen)
179 type: bool default: false
180 --trace_check_elimination (trace check elimination phase)
181 type: bool default: false
182 --trace_hydrogen (trace generated hydrogen to file)
183 type: bool default: false
184 --trace_hydrogen_filter (hydrogen tracing filter)
185 type: string default: *
186 --trace_hydrogen_stubs (trace generated hydrogen for stubs)
187 type: bool default: false
188 --trace_hydrogen_file (trace hydrogen to given file name)
189 type: string default: NULL
190 --trace_phase (trace generated IR for specified phases)
191 type: string default: HLZ
192 --trace_inlining (trace inlining decisions)
193 type: bool default: false
194 --trace_load_elimination (trace load elimination)
195 type: bool default: false
196 --trace_store_elimination (trace store elimination)
197 type: bool default: false
198 --trace_alloc (trace register allocator)
199 type: bool default: false
200 --trace_all_uses (trace all use positions)
201 type: bool default: false
202 --trace_range (trace range analysis)
203 type: bool default: false
204 --trace_gvn (trace global value numbering)
205 type: bool default: false
206 --trace_representation (trace representation types)
207 type: bool default: false
208 --trace_removable_simulates (trace removable simulates)
209 type: bool default: false
210 --trace_escape_analysis (trace hydrogen escape analysis)
211 type: bool default: false
212 --trace_allocation_folding (trace allocation folding)
213 type: bool default: false
214 --trace_track_allocation_sites (trace the tracking of allocation sites)
215 type: bool default: false
216 --trace_migration (trace object migration)
217 type: bool default: false
218 --trace_generalization (trace map generalization)
219 type: bool default: false
220 --stress_pointer_maps (pointer map for every instruction)
221 type: bool default: false
222 --stress_environments (environment for every instruction)
223 type: bool default: false
224 --deopt_every_n_times (deoptimize every n times a deopt point is passed)
226 --deopt_every_n_garbage_collections (deoptimize every n garbage collections)
228 --print_deopt_stress (print number of possible deopt points)
229 type: bool default: false
230 --trap_on_deopt (put a break point before deoptimizing)
231 type: bool default: false
232 --trap_on_stub_deopt (put a break point before deoptimizing a stub)
233 type: bool default: false
234 --deoptimize_uncommon_cases (deoptimize uncommon cases)
235 type: bool default: true
236 --polymorphic_inlining (polymorphic inlining)
237 type: bool default: true
238 --use_osr (use on-stack replacement)
239 type: bool default: true
240 --array_bounds_checks_elimination (perform array bounds checks elimination)
241 type: bool default: true
242 --trace_bce (trace array bounds check elimination)
243 type: bool default: false
244 --array_bounds_checks_hoisting (perform array bounds checks hoisting)
245 type: bool default: false
246 --array_index_dehoisting (perform array index dehoisting)
247 type: bool default: true
248 --analyze_environment_liveness (analyze liveness of environment slots and zap dead values)
249 type: bool default: true
250 --load_elimination (use load elimination)
251 type: bool default: true
252 --check_elimination (use check elimination)
253 type: bool default: true
254 --store_elimination (use store elimination)
255 type: bool default: false
256 --dead_code_elimination (use dead code elimination)
257 type: bool default: true
258 --fold_constants (use constant folding)
259 type: bool default: true
260 --trace_dead_code_elimination (trace dead code elimination)
261 type: bool default: false
262 --unreachable_code_elimination (eliminate unreachable code)
263 type: bool default: true
264 --trace_osr (trace on-stack replacement)
265 type: bool default: false
266 --stress_runs (number of stress runs)
268 --lookup_sample_by_shared (when picking a function to optimize, watch for shared function info, not JSFunction itself)
269 type: bool default: true
270 --cache_optimized_code (cache optimized code for closures)
271 type: bool default: true
272 --flush_optimized_code_cache (flushes the cache of optimized code for closures on every GC)
273 type: bool default: true
274 --inline_construct (inline constructor calls)
275 type: bool default: true
276 --inline_arguments (inline functions with arguments object)
277 type: bool default: true
278 --inline_accessors (inline JavaScript accessors)
279 type: bool default: true
280 --escape_analysis_iterations (maximum number of escape analysis fix-point iterations)
282 --optimize_for_in (optimize functions containing for-in loops)
283 type: bool default: true
284 --concurrent_recompilation (optimizing hot functions asynchronously on a separate thread)
285 type: bool default: true
286 --job_based_recompilation (post tasks to v8::Platform instead of using a thread for concurrent recompilation)
287 type: bool default: false
288 --trace_concurrent_recompilation (track concurrent recompilation)
289 type: bool default: false
290 --concurrent_recompilation_queue_length (the length of the concurrent compilation queue)
292 --concurrent_recompilation_delay (artificial compilation delay in ms)
294 --block_concurrent_recompilation (block queued jobs until released)
295 type: bool default: false
296 --concurrent_osr (concurrent on-stack replacement)
297 type: bool default: true
298 --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.)
299 type: bool default: true
300 --turbo_filter (optimization filter for TurboFan compiler)
301 type: string default: ~
302 --trace_turbo (trace generated TurboFan IR)
303 type: bool default: false
304 --trace_turbo_graph (trace generated TurboFan graphs)
305 type: bool default: false
306 --trace_turbo_cfg_file (trace turbo cfg graph (for C1 visualizer) to a given file name)
307 type: string default: NULL
308 --trace_turbo_types (trace TurboFan's types)
309 type: bool default: true
310 --trace_turbo_scheduler (trace TurboFan's scheduler)
311 type: bool default: false
312 --trace_turbo_reduction (trace TurboFan's various reducers)
313 type: bool default: false
314 --trace_turbo_jt (trace TurboFan's jump threading)
315 type: bool default: false
316 --turbo_asm (enable TurboFan for asm.js code)
317 type: bool default: true
318 --turbo_verify (verify TurboFan graphs at each phase)
319 type: bool default: false
320 --turbo_stats (print TurboFan statistics)
321 type: bool default: false
322 --turbo_types (use typed lowering in TurboFan)
323 type: bool default: true
324 --turbo_source_positions (track source code positions when building TurboFan IR)
325 type: bool default: false
326 --context_specialization (enable context specialization in TurboFan)
327 type: bool default: false
328 --turbo_deoptimization (enable deoptimization in TurboFan)
329 type: bool default: false
330 --turbo_inlining (enable inlining in TurboFan)
331 type: bool default: false
332 --turbo_inlining_intrinsics (enable inlining of intrinsics in TurboFan)
333 type: bool default: false
334 --trace_turbo_inlining (trace TurboFan inlining)
335 type: bool default: false
336 --loop_assignment_analysis (perform loop assignment analysis)
337 type: bool default: true
338 --turbo_profiling (enable profiling in TurboFan)
339 type: bool default: false
340 --turbo_reuse_spill_slots (reuse spill slots in TurboFan)
341 type: bool default: true
342 --turbo_delay_ssa_decon (delay ssa deconstruction in TurboFan register allocator)
343 type: bool default: false
344 --turbo_move_optimization (optimize gap moves in TurboFan)
345 type: bool default: true
346 --turbo_jt (enable jump threading)
347 type: bool default: true
348 --typed_array_max_size_in_heap (threshold for in-heap typed array)
349 type: int default: 64
350 --frame_count (number of stack frames inspected by the profiler)
352 --interrupt_budget (execution budget before interrupt is triggered)
353 type: int default: 6144
354 --type_info_threshold (percentage of ICs that must have type info to allow optimization)
355 type: int default: 25
356 --generic_ic_threshold (max percentage of megamorphic/generic ICs to allow optimization)
357 type: int default: 30
358 --self_opt_count (call count before self-optimization)
359 type: int default: 130
360 --trace_opt_verbose (extra verbose compilation tracing)
361 type: bool default: false
362 --debug_code (generate extra code (assertions) for debugging)
363 type: bool default: false
364 --code_comments (emit comments in code disassembly)
365 type: bool default: false
366 --enable_sse3 (enable use of SSE3 instructions if available)
367 type: bool default: true
368 --enable_sse4_1 (enable use of SSE4.1 instructions if available)
369 type: bool default: true
370 --enable_sahf (enable use of SAHF instruction if available (X64 only))
371 type: bool default: true
372 --enable_avx (enable use of AVX instructions if available)
373 type: bool default: true
374 --enable_fma3 (enable use of FMA3 instructions if available)
375 type: bool default: true
376 --enable_vfp3 (enable use of VFP3 instructions if available)
377 type: bool default: true
378 --enable_armv7 (enable use of ARMv7 instructions if available (ARM only))
379 type: bool default: true
380 --enable_armv8 (enable use of ARMv8 instructions if available (ARM 32-bit only))
381 type: bool default: true
382 --enable_neon (enable use of NEON instructions if available (ARM only))
383 type: bool default: true
384 --enable_sudiv (enable use of SDIV and UDIV instructions if available (ARM only))
385 type: bool default: true
386 --enable_mls (enable use of MLS instructions if available (ARM only))
387 type: bool default: true
388 --enable_movw_movt (enable loading 32-bit constant by means of movw/movt instruction pairs (ARM only))
389 type: bool default: false
390 --enable_unaligned_accesses (enable unaligned accesses for ARMv7 (ARM only))
391 type: bool default: true
392 --enable_32dregs (enable use of d16-d31 registers on ARM - this requires VFP3)
393 type: bool default: true
394 --enable_vldr_imm (enable use of constant pools for double immediate (ARM only))
395 type: bool default: false
396 --force_long_branches (force all emitted branches to be in long mode (MIPS only))
397 type: bool default: false
398 --expose_natives_as (expose natives in global object)
399 type: string default: NULL
400 --expose_debug_as (expose debug in global object)
401 type: string default: NULL
402 --expose_free_buffer (expose freeBuffer extension)
403 type: bool default: false
404 --expose_gc (expose gc extension)
405 type: bool default: false
406 --expose_gc_as (expose gc extension under the specified name)
407 type: string default: NULL
408 --expose_externalize_string (expose externalize string extension)
409 type: bool default: false
410 --expose_trigger_failure (expose trigger-failure extension)
411 type: bool default: false
412 --stack_trace_limit (number of stack frames to capture)
413 type: int default: 10
414 --builtins_in_stack_traces (show built-in functions in stack traces)
415 type: bool default: false
416 --disable_native_files (disable builtin natives files)
417 type: bool default: false
418 --inline_new (use fast inline allocation)
419 type: bool default: true
420 --trace_codegen (print name of functions for which code is generated)
421 type: bool default: false
422 --trace (trace function calls)
423 type: bool default: false
424 --mask_constants_with_cookie (use random jit cookie to mask large constants)
425 type: bool default: true
426 --lazy (use lazy compilation)
427 type: bool default: true
428 --trace_opt (trace lazy optimization)
429 type: bool default: false
430 --trace_opt_stats (trace lazy optimization statistics)
431 type: bool default: false
432 --opt (use adaptive optimizations)
433 type: bool default: true
434 --always_opt (always try to optimize functions)
435 type: bool default: false
436 --always_osr (always try to OSR functions)
437 type: bool default: false
438 --prepare_always_opt (prepare for turning on always opt)
439 type: bool default: false
440 --trace_deopt (trace optimize function deoptimization)
441 type: bool default: false
442 --trace_stub_failures (trace deoptimization of generated code stubs)
443 type: bool default: false
444 --serialize_toplevel (enable caching of toplevel scripts)
445 type: bool default: true
446 --serialize_inner (enable caching of inner functions)
447 type: bool default: false
448 --trace_serializer (print code serializer trace)
449 type: bool default: false
450 --min_preparse_length (minimum length for automatic enable preparsing)
451 type: int default: 1024
452 --max_opt_count (maximum number of optimization attempts before giving up.)
453 type: int default: 10
454 --compilation_cache (enable compilation cache)
455 type: bool default: true
456 --cache_prototype_transitions (cache prototype transitions)
457 type: bool default: true
458 --cpu_profiler_sampling_interval (CPU profiler sampling interval in microseconds)
459 type: int default: 1000
460 --trace_debug_json (trace debugging JSON request/response)
461 type: bool default: false
462 --trace_js_array_abuse (trace out-of-bounds accesses to JS arrays)
463 type: bool default: false
464 --trace_external_array_abuse (trace out-of-bounds-accesses to external arrays)
465 type: bool default: false
466 --trace_array_abuse (trace out-of-bounds accesses to all arrays)
467 type: bool default: false
468 --enable_liveedit (enable liveedit experimental feature)
469 type: bool default: true
470 --hard_abort (abort by crashing)
471 type: bool default: true
472 --stack_size (default size of stack region v8 is allowed to use (in kBytes))
473 type: int default: 984
474 --max_stack_trace_source_length (maximum length of function source code printed in a stack trace.)
475 type: int default: 300
476 --always_inline_smi_code (always inline smi code in non-opt code)
477 type: bool default: false
478 --min_semi_space_size (min size of a semi-space (in MBytes), the new space consists of twosemi-spaces)
480 --target_semi_space_size (target size of a semi-space (in MBytes) before triggering a GC)
482 --max_semi_space_size (max size of a semi-space (in MBytes), the new space consists of twosemi-spaces)
484 --semi_space_growth_factor (factor by which to grow the new space)
486 --experimental_new_space_growth_heuristic (Grow the new space based on the percentage of survivors instead of their absolute value.)
487 type: bool default: false
488 --max_old_space_size (max size of the old space (in Mbytes))
490 --initial_old_space_size (initial old space size (in Mbytes))
492 --max_executable_size (max size of executable memory (in Mbytes))
494 --gc_global (always perform global GCs)
495 type: bool default: false
496 --gc_interval (garbage collect after <n> allocations)
497 type: int default: -1
498 --trace_gc (print one trace line following each garbage collection)
499 type: bool default: false
500 --trace_gc_nvp (print one detailed trace line in name=value format after each garbage collection)
501 type: bool default: false
502 --trace_gc_ignore_scavenger (do not print trace line after scavenger collection)
503 type: bool default: false
504 --trace_idle_notification (print one trace line following each idle notification)
505 type: bool default: false
506 --trace_idle_notification_verbose (prints the heap state used by the idle notification)
507 type: bool default: false
508 --print_cumulative_gc_stat (print cumulative GC statistics in name=value format on exit)
509 type: bool default: false
510 --print_max_heap_committed (print statistics of the maximum memory committed for the heap in name=value format on exit)
511 type: bool default: false
512 --trace_gc_verbose (print more details following each garbage collection)
513 type: bool default: false
514 --trace_fragmentation (report fragmentation for old pointer and data pages)
515 type: bool default: false
516 --collect_maps (garbage collect maps from which no objects can be reached)
517 type: bool default: true
518 --weak_embedded_maps_in_optimized_code (make maps embedded in optimized code weak)
519 type: bool default: true
520 --weak_embedded_objects_in_optimized_code (make objects embedded in optimized code weak)
521 type: bool default: true
522 --flush_code (flush code that we expect not to use again (during full gc))
523 type: bool default: true
524 --flush_code_incrementally (flush code that we expect not to use again (incrementally))
525 type: bool default: true
526 --trace_code_flushing (trace code flushing progress)
527 type: bool default: false
528 --age_code (track un-executed functions to age code and flush only old code (required for code flushing))
529 type: bool default: true
530 --incremental_marking (use incremental marking)
531 type: bool default: true
532 --incremental_marking_steps (do incremental marking steps)
533 type: bool default: true
534 --concurrent_sweeping (use concurrent sweeping)
535 type: bool default: true
536 --trace_incremental_marking (trace progress of the incremental marking)
537 type: bool default: false
538 --track_gc_object_stats (track object counts and memory usage)
539 type: bool default: false
540 --heap_profiler_trace_objects (Dump heap object allocations/movements/size_updates)
541 type: bool default: false
542 --use_idle_notification (Use idle notification to reduce memory footprint.)
543 type: bool default: true
544 --use_ic (use inline caching)
545 type: bool default: true
546 --trace_ic (trace inline cache state transitions)
547 type: bool default: false
548 --native_code_counters (generate extra code for manipulating stats counters)
549 type: bool default: false
550 --always_compact (Perform compaction on every full GC)
551 type: bool default: false
552 --never_compact (Never perform compaction on full GC - testing only)
553 type: bool default: false
554 --compact_code_space (Compact code space on full non-incremental collections)
555 type: bool default: true
556 --incremental_code_compaction (Compact code space on full incremental collections)
557 type: bool default: true
558 --cleanup_code_caches_at_gc (Flush inline caches prior to mark compact collection and flush code caches in maps during mark compact cycle.)
559 type: bool default: true
560 --use_marking_progress_bar (Use a progress bar to scan large objects in increments when incremental marking is active.)
561 type: bool default: true
562 --zap_code_space (Zap free memory in code space with 0xCC while sweeping.)
563 type: bool default: true
564 --random_seed (Default seed for initializing random generator (0, the default, means to use system random).)
566 --trace_weak_arrays (trace WeakFixedArray usage)
567 type: bool default: false
568 --track_prototype_users (keep track of which maps refer to a given prototype object)
569 type: bool default: false
570 --use_verbose_printer (allows verbose printing)
571 type: bool default: true
572 --allow_natives_syntax (allow natives syntax)
573 type: bool default: false
574 --trace_parse (trace parsing and preparsing)
575 type: bool default: false
576 --trace_sim (Trace simulator execution)
577 type: bool default: false
578 --debug_sim (Enable debugging the simulator)
579 type: bool default: false
580 --check_icache (Check icache flushes in ARM and MIPS simulator)
581 type: bool default: false
582 --stop_sim_at (Simulator stop after x number of instructions)
584 --sim_stack_alignment (Stack alingment in bytes in simulator (4 or 8, 8 is default))
586 --sim_stack_size (Stack size of the ARM64 and MIPS64 simulator in kBytes (default is 2 MB))
587 type: int default: 2048
588 --log_regs_modified (When logging register values, only print modified registers.)
589 type: bool default: true
590 --log_colour (When logging, try to use coloured output.)
591 type: bool default: true
592 --ignore_asm_unimplemented_break (Don't break for ASM_UNIMPLEMENTED_BREAK macros.)
593 type: bool default: false
594 --trace_sim_messages (Trace simulator debug messages. Implied by --trace-sim.)
595 type: bool default: false
596 --stack_trace_on_illegal (print stack trace when an illegal exception is thrown)
597 type: bool default: false
598 --abort_on_uncaught_exception (abort program (dump core) when an uncaught exception is thrown)
599 type: bool default: false
600 --randomize_hashes (randomize hashes to avoid predictable hash collisions (with snapshots this option cannot override the baked-in seed))
601 type: bool default: true
602 --hash_seed (Fixed seed to use to hash property keys (0 means random)(with snapshots this option cannot override the baked-in seed))
604 --profile_deserialization (Print the time it takes to deserialize the snapshot.)
605 type: bool default: false
606 --regexp_optimization (generate optimized regexp code)
607 type: bool default: true
608 --testing_bool_flag (testing_bool_flag)
609 type: bool default: true
610 --testing_maybe_bool_flag (testing_maybe_bool_flag)
611 type: maybe_bool default: unset
612 --testing_int_flag (testing_int_flag)
613 type: int default: 13
614 --testing_float_flag (float-flag)
615 type: float default: 2.5
616 --testing_string_flag (string-flag)
617 type: string default: Hello, world!
618 --testing_prng_seed (Seed used for threading test randomness)
619 type: int default: 42
620 --testing_serialization_file (file in which to serialize heap)
621 type: string default: /tmp/serdes
622 --startup_blob (Write V8 startup blob file. (mksnapshot only))
623 type: string default: NULL
624 --profile_hydrogen_code_stub_compilation (Print the time it takes to lazily compile hydrogen code stubs.)
625 type: bool default: false
626 --predictable (enable predictable mode)
627 type: bool default: false
628 --help (Print usage message, including flags, on console)
629 type: bool default: true
630 --dump_counters (Dump counters on exit)
631 type: bool default: false
632 --debugger (Enable JavaScript debugger)
633 type: bool default: false
634 --map_counters (Map counters to a file)
635 type: string default:
636 --js_arguments (Pass all remaining arguments to the script. Alias for "--".)
637 type: arguments default:
638 --gdbjit (enable GDBJIT interface (disables compacting GC))
639 type: bool default: false
640 --gdbjit_full (enable GDBJIT interface for all code objects)
641 type: bool default: false
642 --gdbjit_dump (dump elf objects with debug info to disk)
643 type: bool default: false
644 --gdbjit_dump_filter (dump only objects containing this substring)
645 type: string default:
646 --force_marking_deque_overflows (force overflows of marking deque by reducing it's size to 64 words)
647 type: bool default: false
648 --stress_compaction (stress the GC compactor to flush out bugs (implies --force_marking_deque_overflows))
649 type: bool default: false
650 --log (Minimal logging (no API, code, GC, suspect, or handles samples).)
651 type: bool default: false
652 --log_all (Log all events to the log file.)
653 type: bool default: false
654 --log_api (Log API events to the log file.)
655 type: bool default: false
656 --log_code (Log code events to the log file without profiling.)
657 type: bool default: false
658 --log_gc (Log heap samples on garbage collection for the hp2ps tool.)
659 type: bool default: false
660 --log_handles (Log global handle events.)
661 type: bool default: false
662 --log_snapshot_positions (log positions of (de)serialized objects in the snapshot.)
663 type: bool default: false
664 --log_suspect (Log suspect operations.)
665 type: bool default: false
666 --prof (Log statistical profiling information (implies --log-code).)
667 type: bool default: false
668 --prof_browser_mode (Used with --prof, turns on browser-compatible mode for profiling.)
669 type: bool default: true
670 --log_regexp (Log regular expression execution.)
671 type: bool default: false
672 --logfile (Specify the name of the log file.)
673 type: string default: v8.log
674 --logfile_per_isolate (Separate log files for each isolate.)
675 type: bool default: true
676 --ll_prof (Enable low-level linux profiler.)
677 type: bool default: false
678 --perf_basic_prof (Enable perf linux profiler (basic support).)
679 type: bool default: false
680 --perf_jit_prof (Enable perf linux profiler (experimental annotate support).)
681 type: bool default: false
682 --gc_fake_mmap (Specify the name of the file for fake gc mmap used in ll_prof)
683 type: string default: /tmp/__v8_gc__
684 --log_internal_timer_events (Time internal events.)
685 type: bool default: false
686 --log_timer_events (Time events including external callbacks.)
687 type: bool default: false
688 --log_instruction_stats (Log AArch64 instruction statistics.)
689 type: bool default: false
690 --log_instruction_file (AArch64 instruction statistics log file.)
691 type: string default: arm64_inst.csv
692 --log_instruction_period (AArch64 instruction statistics logging period.)
693 type: int default: 4194304
694 --redirect_code_traces (output deopt information and disassembly into file code-<pid>-<isolate id>.asm)
695 type: bool default: false
696 --redirect_code_traces_to (output deopt information and disassembly into the given file)
697 type: string default: NULL
698 --hydrogen_track_positions (track source code positions when building IR)
699 type: bool default: false
700 --trace_elements_transitions (trace elements transitions)
701 type: bool default: false
702 --trace_creation_allocation_sites (trace the creation of allocation sites)
703 type: bool default: false
704 --print_code_stubs (print code stubs)
705 type: bool default: false
706 --test_secondary_stub_cache (test secondary stub cache by disabling the primary one)
707 type: bool default: false
708 --test_primary_stub_cache (test primary stub cache by disabling the secondary one)
709 type: bool default: false
710 --print_code (print generated code)
711 type: bool default: false
712 --print_opt_code (print optimized code)
713 type: bool default: false
714 --print_unopt_code (print unoptimized code before printing optimized code based on it)
715 type: bool default: false
716 --print_code_verbose (print more information for code)
717 type: bool default: false
718 --print_builtin_code (print generated code for builtins)
719 type: bool default: false
720 --sodium (print generated code output suitable for use with the Sodium code viewer)
721 type: bool default: false
722 --print_all_code (enable all flags related to printing code)
723 type: bool default: false
725 .SH RESOURCES AND DOCUMENTATION
727 See the website for documentation http://iojs.org/
729 Mailing list: http://groups.google.com/group/nodejs
731 IRC: irc.freenode.net #io.js