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path: root/erts/emulator/beam/dist.c
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2010-12-15Remove ancient distribution message DOP_NODE_LINK from all codePatrik Nyblom
2010-12-14Teach VM not to dump core on bad dist message structurePatrik Nyblom
2010-11-02Be less eager to set dist entry in busy stateRickard Green
The runtime system is now less eager to suspend processes sending messages over the distribution. The default value of the distribution buffer busy limit has also been increased from 128 KB to 1 MB. This in order to improve throughput.
2010-11-02Add flag-based setting for the distribution buffer busy limitScott Lystig Fritchie
Id: OTP-8912 This patch creates a new family of flags with the "+z" prefix. It further creates a new configuration option called "dbbl" (which is the first letter of the name dist_buf_busy_limit). Example usage of this flag would be "+zdbbl 1048576". This patch creates an adjustable buffer limit for the amount of data that may be buffered by the erlang distribution code (in dist.c specifically). Before this patch, this hard-coded constant was used: #define ERTS_DE_BUSY_LIMIT (128*1024) When large binaries are transmitted between nodes (or simply a lot of medium-sized binaries), it is very easy to hit the old 128KB limit. Processes that use the erlang:system_monitor() BIF to monitor system events can be spammed by {monitor, busy_dist_port, ...} message tuples at rates of tens to even hundreds of messages/second. A larger buffer limit will allow processes to buffer more outgoing messages over the distribution. When the buffer limit has been reached, sending processes will be suspended until the buffer size has shrunk. The buffer limit is per distribution channel. A higher limit will give lower latency and higher throughput at the expense of higher memory usage. A variation of this patch has been in commercial production use in at least two companies that the author is aware of. Larger buffer values can reduce the number of {monitor, busy_dist_port, ...} system messages drastically, lower overall messaging latencies, and prevent false timeouts and 'nodedown' messages in extremely busy Mnesia systems. Test suite: there are two tests: a. In erlexec_SUITE.erl to test basic set & get of the value b. In distribution_SUITE.erl, to verify that setting +zdbbl very low will actually change behavior.
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.
2010-03-22Merge branch 'pan/otp_8332_halfword' into devErlang/OTP
* pan/otp_8332_halfword: Teach testcase in driver_suite the new prototype for driver_async wx: Correct usage of driver callbacks from wx thread Adopt the new (R13B04) Nif functionality to the halfword codebase Support monitoring and demonitoring from driver threads Fix further test-suite problems Correct the VM to work for more test suites Teach {wordsize,internal|external} to system_info/1 Make tracing and distribution work Turn on instruction packing in the loader and virtual machine Add the BeamInstr data type for loaded BEAM code Fix the BEAM dissambler for the half-word emulator Store pointers to heap data in 32-bit words Add a custom mmap wrapper to force heaps into the lower address range Fit all heap data into the 32-bit address range
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.
2010-03-10Fit all heap data into the 32-bit address rangePatrik Nyblom
This is the first step in the implementation of the half-word emulator, a 64-bit emulator where all pointers to heap data will be stored in 32-bit words. Code specific for this emulator variant is conditionally compiled when the HALFWORD_HEAP define has a non-zero value. First force all pointers to heap data to fall into a single 32-bit range, but still store them in 64-bit words. Temporary term data stored on C stack is moved into scheduler specific storage (allocated as heaps) and macros are added to make this happen only in emulators where this is needed. For a vanilla VM the temporary terms are still stored on the C stack.
2009-11-20The R13B03 release.OTP_R13B03Erlang/OTP