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2012-11-22Teach erts_bs_append not to dump corePatrik Nyblom
When erts_bs_append() calls the garbage collector, it has set the PB_ACTIVE_WRITER flag in the ProcBin for the binary object is about to be appended to. Therefore, it is expected that the garbage collector should neither move nor shrink the binary object. But if the garbage collector does a minor collection (thereby clearing the PB_ACTIVE_WRITER flag in the ProcBin) and there is still not enough heap space, there will be a second major garbage collection. During the major collection (since the the PB_ACTIVE_WRITER flag was cleared), the binary object may be shrunk or moved (depending on sizes and how many other writable binaries there are in the process). Avoid the problem by clearing the PB_ACTIVE_WRITER flags in a separate pass after the garbage collection(s). Thanks to Denis Titoruk for helping us find this bug.
2012-03-30Update copyright yearsBjörn-Egil Dahlberg
2012-03-22Ifdef all dynamic trace codePatrik Nyblom
2012-03-22Change to more specific configure options for dtracePatrik Nyblom
2012-03-22Add user tag spreading functionality to VM and use in filePatrik Nyblom
User tags in a dynamic trace enabled VM are spread throughout the system in the same way as seq_trace tokens. This is used by the file module and various other modules to get hold of the tag from the user process without changing the protocol.
2012-03-22Update dtrace for changes in R15Björn-Egil Dahlberg
2012-03-22Add DTrace support for OS X, Solaris, and Linux (via SystemTap), 3/4Scott Lystig Fritchie
Add probes to the virtual machine, except (mostly) the efile_drv.c driver and other file I/O-related source files.
2012-02-14Merge branch 'jz/reduce-smp-locking-time-range' into maintHenrik Nord
* jz/reduce-smp-locking-time-range: erts: reduce smp locking time range in erts_garbage_collect OTP-9912
2011-12-20erts: reduce smp locking time range in erts_garbage_collectJovi Zhang
get_now should be use out of process status locking, then it can reduce smp locking time range in here.
2011-12-19erts: Make GC tolerate hibernated process without hipe stackSverker Eriksson
Seen causing segv on sparc with hibernate_native_SUITE:basic: nstack_walk_frame_ra (nsp=0x0, sdesc=0x6c8f2c) at hipe_risc_gc.h:105 gensweep_nstack (p=0x6a6930, ptr_old_htop=0xffbfea50, ptr_n_htop=0xffbfea4c) at hipe/hipe_gc.c:224 do_minor (p=0x6a6930, new_sz=233, objv=0x6a6984, nobj=3) at beam/erl_gc.c:949 minor_collection (p=0x6a6930, need=3, objv=0x6a6984, nobj=3, recl=0xffbfece4) at beam/erl_gc.c:811 erts_garbage_collect (p=0x6a6930, need=3, objv=0x6a6984, nobj=3) at beam/erl_gc.c:379 erts_send_message (sender=0x6a6048, receiver=0x6a6930, receiver_locks=0xffbfedf8, message=6132762, flags=0) at beam/erl_message.c:922 do_send (p=0x6a6048, to=515, msg=6132762, suspend=1) at beam/bif.c:2052 erl_send (p=0x6a6048, to=515, msg=6132762) at beam/bif.c:2151 send_2 (A__p=0x6a6048, BIF__ARGS=0x6a609c) at beam/bif.c:2146 nbif_send_2 ()
2011-11-17Allow refc binaries in literal poolsBjörn Gustavsson
To simplify the implementation of literal pools (constant pools) for the R12 release, a shortcut was taken regarding binaries -- all binaries would be stored as heap binaries regardless of size. To allow a module containing literals to be unloaded, literal terms are copied when sent to another process. That means that huge literal binaries will also be copied if they are sent to another process, which could be surprising. Another problem is that the arity field in the header for the heap object may not be wide enough to handle big binaries. Therefore, bite the bullet and allow refc binaries to be stored in literal pools. In short, the following need to be changed: * Each loaded module needs a MSO list, linking all refc binaries in the literal pool. * When check_process_code/2 copies literals to a process heap, it must link each referenced binary into the MSO list for the process and increment the reference counter for the binary. * purge_module/1 must decrement the reference counter for each refc binary in the literal pool.
2011-11-13Merge branch 'rickard/thr-progress-block/OTP-9631'Rickard Green
* rickard/thr-progress-block/OTP-9631: Replace system block with thread progress block
2011-11-13Replace system block with thread progress blockRickard Green
The ERTS internal system block functionality has been replaced by new functionality for blocking the system. The old system block functionality had contention issues and complexity issues. The new functionality piggy-backs on thread progress tracking functionality needed by newly introduced lock-free synchronization in the runtime system. When the functionality for blocking the system isn't used there is more or less no overhead at all. This since the functionality for tracking thread progress is there and needed anyway.
2011-10-26erts-hipe: Fix new trap conventions for x86, amd64 and ppcSverker Eriksson
2011-10-26Store the trap arguments in the X register arrayBjörn Gustavsson
Store arguments for a trap in the X register array to allow traps to have any number of arguments.
2011-08-15fix 64-bit issues in the garbage collectionRichard Carlsson
We discovered that if a single Erlang process tried to grow above 32 GB (i.e., more 64-bit words than can be counted by a 32-bit number), the VM failed to find the next larger heap size, even though there were plenty more heap sizes left to pick from and even though we had a lot more memory available on the machine. (Obviously, this is only applicable on 64-bit Erlang.) It turned out to be due to some 'int' variables in the heap resizing parts of erl_gc.c not being properly updated to 'Uint' or 'Sint'. Once that was fixed, I got segfaults instead as soon as the heap got larger than 2^32 words, due to even more 'int' declarations in the same file, but now in the GC code. After fixing this as well, I successfully ran an Erlang node in which a single Erlang process had a heap so large that I'm not at liberty to divulge the exact size, but I think the scientific term is "humongous", and I'm confident that there are no further immediate problems with very very large individual process heaps.
2011-05-06Merge branch 'ms/beam-fix-format-specifiers-in-erl_exit-msg' into devHenrik Nord
* ms/beam-fix-format-specifiers-in-erl_exit-msg: Fix format specifiers in erl_exit messages OTP-9262
2011-04-07Fix format specifiers in erl_exit messagesMichael Santos
Fix an error message by using an unsigned integer specifier as seen in a tweet by @metabrew: #erlang VM crashed with "no next heap size found: -2090496108, offset 0", suddenly allocated all available RAM Also correct mis-typed string formats in bif.c.
2011-03-16erts: Remove unused variablesTuncer Ayaz
2011-03-10Update copyright yearsSverker Eriksson
2011-01-29Fix several bugs related to hibernate/3 and HiPEPaul Guyot
This commit fixes four related bugs: - calling hibernate/3 using a dynamic call would fail with badarg as hibernate/3 as a BIF was not implemented. hibernate/3 is generally provided as a Beam instruction, and code is translated to use this instruction when loaded. - calling hibernate/3 from HiPE would fail with badarg because this would call the aforementioned BIF which was not implemented. - calling hibernate/3 with some HiPE-native garbage in the process heap would randomly crash at the next garbage collect. This bug only happened in a complex, yet reproduceable scenarios, where native code calls beam code that calls hibernate/3, and the process has some garbage when being hibernated and the process generates garbage when awaken. - when entering HiPE, the process current_function can be set and be inaccurate. The fix is three folded: - hibernate_3 BIF now actually works instead of throwing a badarg. While hibernate_3 BIF was (usually) not called from BEAM, it is called from HiPE. hibernate behaviour is very close to the scheduler and this is why it is implemented as an instruction in BEAM. The fix consists in doing the actual hibernation (through the now exported erts_hibernate function) and setting the process flag to TRAP as well as the process status to P_WAITING. On BIF epilogue in both BEAM and HiPE, this status is tested on TRAP and if set, the scheduler is invoked. The i_hibernate instruction and translation code is now redundant and could be deleted. - hibernation now also empties the HiPE native stack, with a new function hipe_empty_nstack provided by Mikael Pettersson. - when entering HiPE through hipe_mode_switch, p->current is cleared, as suggested by Mikael Pettersson. p->current normally hold a pointer to the {M,F,A} of the current function if it exists. When hibernating, it is set to {erlang,hibernate,3}, and all stdlib hibernate tests (gen_server_SUITE:hibernate/1, proc_lib_suite:hibernate/1, etc.) actually rely on this information. Clearing p->current fixes the tests and avoids the surprise one might have when querying the process info of a process that hibernated and woke up in a native function. Non-regression tests are provided, a test for the dynamic call as well as a Makefile-handled duplication of the hibernate_SUITE into hibernate_native_SUITE for the HiPE case.
2010-12-15Use new atomic types in emulatorRickard Green
2010-08-12Increase vheap counter to Uint64Björn-Egil Dahlberg
This will reduce the risk of integer wrapping in bin vheap counting. The vheap size series will now use the golden ratio instead of doubling and fibonacci sequences. OTP #8730
2010-08-12Fix wrapping in next vheap calculationBjörn-Egil Dahlberg
OTP #8730
2010-07-22Mending halfword heap emulatorSverker Eriksson
2010-07-20One off-heap list, to eliminate two words per ETS object.Sverker Eriksson
Merging the three off-heap lists (binaries, funs and externals) into one list. This reduces memory consumption by two words (pointers) per ETS object.
2010-06-03OTP-8555 Send message from NIFSverker Eriksson
New NIF features: Send messages from a NIF, or from thread created by NIF, to any local process (enif_send) Store terms between NIF calls (enif_alloc_env, enif_make_copy) Create binary terms with user defined memory management (enif_make_resource_binary)
2010-03-10Store pointers to heap data in 32-bit wordsPatrik Nyblom
Store Erlang terms in 32-bit entities on the heap, expanding the pointers to 64-bit when needed. This works because all terms are stored on addresses in the 32-bit address range (the 32 most significant bits of pointers to term data are always 0). Introduce a new datatype called UWord (along with its companion SWord), which is an integer having the exact same size as the machine word (a void *), but might be larger than Eterm/Uint. Store code as machine words, as the instructions are pointers to executable code which might reside outside the 32-bit address range. Continuation pointers are stored on the 32-bit stack and hence must point to addresses in the low range, which means that loaded beam code much be placed in the low 32-bit address range (but, as said earlier, the instructions themselves are full words). No Erlang term data can be stored on C stacks (enforced by an earlier commit). This version gives a prompt, but test cases still fail (and dump core). The loader (and emulator loop) has instruction packing disabled. The main issues has been in rewriting loader and actual virtual machine. Subsystems (like distribution) does not work yet.
2010-01-13Improve binary garbage collectionBjörn-Egil Dahlberg
The garbage collector in r13b03 is too aggressive in some cases. This commit raises the level of default initial allowed binary garbage (virtual heap for binaries) before collecting from 233 words to 46368 words (181 kB on 32-bit). A new option, min_bin_vheap_size, has been added to spawn_opt, system_flag and process_flag can be used to change the default values. The option can also be used with system_info and process_info to inspect the values. For symmetry the option min_heap_size has been added to the above functions where it was previously missing. Add testcases for min_bin_vheap_size and min_heap_size for functions process_flag/2, process_info/2, system_info/2 and spawn_opt/2.
2010-01-13OTP-8240 Improved GC performance after BIF/NIF call when a lot of heapSverker Eriksson
fragments was created. This will mainly benefit NIFs that return large compound terms.
2009-11-20The R13B03 release.OTP_R13B03Erlang/OTP