- Boost-users - lists.preview.boost.org

Missing thread symbols when compiling from source: join(), ~thread() and start_thread()
by Edward Kornkven 22 Aug '15

22 Aug '15

Hello, I am trying to build Boost for linking with an application. I do not have admin access and there is an existing older Boost version in the system area. My problem is that there are three thread symbols that do not get defined by my build process: undefined reference to `boost::thread::join()' undefined reference to `boost::thread::~thread()' undefined reference to `boost::thread::start_thread()' Google reveals that this problem has been around for a while but the usual remedy is to install some binary or other. I need to build from source but for the life of me I can't understand what I am doing wrong that these symbols are not being defined. I can search everything that is being built using "nm" and they just aren't there. I think I am using a pretty standard build process of first building Boost.Build, then the rest: ./bootstrap.sh --with-toolset=gcc ./b2 install --prefix=${PREFIX} ${PREFIX}/bin/b2 --prefix=${PREFIX} toolset=gcc install I have geared down to various forms of magic: stage and then install, --without-thread followed by --with-thread, but I must be missing something basic about these libraries which I do not have occasion to use routinely. The build scripts are a bit opaque but don't indicate any errors. I am a little surprised that this isn't in an FAQ somewhere but maybe not many of us build Boost from source. Thanks for any assistance. Ed

1 0

build boost with specific msvcrt.lib
by Abhay Mhatre 21 Aug '15

21 Aug '15

is it possible to provide specific msvcrt.lib while building boost. It uses default one and my build system uses the one specified in build system. this causes heap corruption at the end of program termination. thanks

5 8

Building Boost 1.59.0 on Solaris 11 with Solaris Studio 12.4
by Leo Carreon 21 Aug '15

21 Aug '15

Hi Boosters, I have been attempting to build Boost 1.59.0 on Solaris 11 using Solaris Studio 12.4 in C++11 mode. So far, I have managed to locate on the web solutions to 3 issues. Now I’m down to 22 targets failing to build. Has anyone else attempted to do the same? I would appreciate it if you could share some of your fixes if you have any. Has anyone reported that they have been able to cleanly build in this environment? Kind regards, Leo

2 7

Regarding dijkstra_shortest_path() in boost graph library
by Rohith Reddy 20 Aug '15

20 Aug '15

Hello there, I started using Boost graph library recently for one of my projects.I was trying to implement dijkstra's shortest path algorithm with the help of the following function, dijkstra_shortest_paths (G, vertex(a, G), distance_map(make_iterator_property_map(distance.begin(), vertex_id, distance[0])). predecessor_map(make_iterator_property_map(parent.begin(), vertex_id, parent[0])). visitor(make_dijkstra_visitor(copy_graph(G_copy, on_examine_edge())))); But while comparing the definition of the function as in http://www.boost.org/doc/libs/1_55_0/libs/graph/doc/dijkstra_shortest_paths…, to the above written function,it doesnt make sense, especially the third argument of the above written function.Can anyone help me with this? Thanks in advance.

1 0

Encoding with read_xml()
by ashish g 20 Aug '15

20 Aug '15

Hi I was looking into using the function 'read_xml()' which parses an xml file and populates a ptree. However I had a couple of questions which I couldnt find documentation for. 1. Is the encoding of the xml file format preserverd when the data is stored into the ptree. i.e lets say I have an xml file in utf-8 format. Are the strings inside my ptree utf-8 encoded as well? Or is it converted to system default encoding? 2. Passing the locale information as an argument to read_xml(), what effect does it have? I believe it assumes the xml file is formatted using the locale encoding, or uses system locale encoding if no arg is passed. Is this true even if my xml 's first line explicitly states that it uses and encoding diff from the system encoding. for eg: lets say im on windows with 1252 encoding. My xml file is utf-8, and is specified on the first line. If i call read_xml() on this file, without passing a locale as arg, does it use system 1252 encoding to parse the file or utf-8? Any pointers would be very helpful. Thank you -- *Ashish Gudla*

1 0

[MSM] Stack blown with deferred events (1.59.0)
by Tom Gibson 20 Aug '15

20 Aug '15

Hi Boost-Users and Christophe, I'm having an issue when using MSM's deferred events feature. I've written a very basic example of a state machine, simulating batching upon receipt of events using the deferred message queue as a buffer, and then handling the events in another state once a watermark has been hit. This however, is not working as well as I'd hoped. I've made the batch size configurable with a constructor variable on the state machine, and am using guards in the transition table to do the checking. Whilst functionally this works, when I set a reasonably large batch size (10,000), the process cores. I've done a bit of digging in gdb, and it appears that the stack is being blown. `ulimit -s shows 8192` as my stack limit, raising this to 16384 with a 10k batch size works, although the performance is pretty bad. Raising the batch size to beyond the stack limit once again breaks MSM. I've attached my test program, and am compiling and running locally with: ``` clang++ -std=c++11 -o batcher -g batch_test.cpp ./batcher <batch size> [total events=100000] ``` To summarize, I've a few questions with my scenario. 1. Am I using the deferred events feature correctly? I believe I've followed the documentation, but it is entirely possible there's something I'm missing! 2. Is this a valid use case for the deferred events feature, or something that wouldn't be recommended? Handling of deferred events seems to be fine normally, but with a large number of events, the performance does seem to suffer significantly. For example, `time` shows a batch size of 10 taking 0.470s, with a batch size of 5000 taking 24.415s. This gap is closed significantly when built with with -02 due to inlining, but its still significant. 3. The stack blowing to me implies recursion when items are processed from the deferred events queue (rather than a linear iteration over the container (deque in my case)). I've tried to follow this in the MSM code, but it's heavy stuff. In this scenario, is it possible I would be better to implement my own queuing mechanism? Thanks, Tom

1 0

Errors and failed targets when building [filesystem]
by morbid code 19 Aug '15

19 Aug '15

Hi guys, I am extremely new at boost. I downloaded the latest version and I did the following: I am using windows7 64 bit and GCC 5.1. I opened command line, went to C:\boost\tools\build and ran the command: bootstrap gcc The output is: Bootstrapping the build engine execcmd.c: In function 'onintr': execcmd.c:120:5: warning: implicit declaration of function 'out_printf' [-Wimpli cit-function-declaration] out_printf( "...interrupted\n" ); ^ execnt.c: In function 'maxline': execnt.c:524:12: warning: type defaults to 'int' in declaration of 'result' [-Wi mplicit-int] static result; ^ make.c: In function 'make': make.c:132:13: warning: implicit declaration of function 'out_printf' [-Wimplici t-function-declaration] out_printf( "...found %d target%s...\n", counts->targets, ^ make.c: In function 'make0': make.c:735:13: warning: implicit declaration of function 'out_flush' [-Wimplicit -function-declaration] out_flush(); ^ modules/path.c: In function 'path_exists': modules/path.c:16:12: warning: implicit declaration of function 'file_query' [-W implicit-function-declaration] return file_query( list_front( lol_get( frame->args, 0 ) ) ) ? ^ Bootstrapping is done. To build, run: .\b2 --prefix=DIR install Then I ran: b2 --prefix=DIR toolset=gcc install According to the long output 322 targets have been updated. I put the path C:\boost\tools\build\DIR\bin to the environment variables. Lastly, I ran: b2 --build-dir=C:\boost-filesystem toolset=gcc --with-filesystem stage The output: ...found 8 targets... ...updating 5 targets... common.mkdir C:\boost-filesystem\boost common.mkdir C:\boost-filesystem\boost\architecture common.mkdir C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0 common.mkdir C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0\debug gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0\debug\32. o libs\config\checks\architecture\32.cpp:9:36: error: size of array 'test' is negative int test[sizeof(void*) == 4? 1 : -1]; ^ "g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -g -c -o "C:\boost-fil esystem\boost\architecture\gcc-mingw-5.1.0\debug\32.o" "libs\config\checks\archi tecture\32.cpp" ...failed gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0 \debug\32.o... ...failed updating 1 target... ...updated 4 targets... Performing configuration checks - 32-bit : no ...found 2 targets... ...updating 1 target... gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0\debug\64. o ...updated 1 target... - 64-bit : yes ...found 2 targets... ...updating 1 target... gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0\debug\arm .o libs\config\checks\architecture\arm.cpp:13:2: error: #error "Not ARM" #error "Not ARM" ^ "g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -g -c -o "C:\boost-fil esystem\boost\architecture\gcc-mingw-5.1.0\debug\arm.o" "libs\config\checks\arch itecture\arm.cpp" ...failed gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0 \debug\arm.o... ...failed updating 1 target... - arm : no ...found 2 targets... ...updating 1 target... gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0\debug\mip s1.o libs\config\checks\architecture\mips1.cpp:10:2: error: #error "Not MIPS1" #error "Not MIPS1" ^ "g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -g -c -o "C:\boost-fil esystem\boost\architecture\gcc-mingw-5.1.0\debug\mips1.o" "libs\config\checks\ar chitecture\mips1.cpp" ...failed gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0 \debug\mips1.o... ...failed updating 1 target... - mips1 : no ...found 2 targets... ...updating 1 target... gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0\debug\pow er.o libs\config\checks\architecture\power.cpp:13:2: error: #error "Not PPC" #error "Not PPC" ^ "g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -g -c -o "C:\boost-fil esystem\boost\architecture\gcc-mingw-5.1.0\debug\power.o" "libs\config\checks\ar chitecture\power.cpp" ...failed gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0 \debug\power.o... ...failed updating 1 target... - power : no ...found 2 targets... ...updating 1 target... gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0\debug\spa rc.o libs\config\checks\architecture\sparc.cpp:10:2: error: #error "Not SPARC" #error "Not SPARC" ^ "g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -g -c -o "C:\boost-fil esystem\boost\architecture\gcc-mingw-5.1.0\debug\sparc.o" "libs\config\checks\ar chitecture\sparc.cpp" ...failed gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0 \debug\sparc.o... ...failed updating 1 target... - sparc : no ...found 2 targets... ...updating 1 target... gcc.compile.c++ C:\boost-filesystem\boost\architecture\gcc-mingw-5.1.0\debug\x86 .o ...updated 1 target... - x86 : yes ...found 3 targets... ...updating 3 targets... common.mkdir C:\boost-filesystem\boost\bin.v2 link.touch C:\boost-filesystem\boost\bin.v2\test-symlink-source link.mklink C:\boost-filesystem\boost\bin.v2\test-symlink symbolic link created for C:\boost-filesystem\boost\bin.v2\test-symlink <<===>> test-symlink-source ...updated 3 targets... - symlinks supported : yes ...found 1 target... ...updating 1 target... config-cache.write C:\boost-filesystem\boost\bin.v2\project-cache.jam ...updated 1 target... Component configuration: - atomic : not building - chrono : not building - container : not building - context : not building - coroutine : not building - coroutine2 : not building - date_time : not building - exception : not building - filesystem : building - graph : not building - graph_parallel : not building - iostreams : not building - locale : not building - log : not building - math : not building - mpi : not building - program_options : not building - python : not building - random : not building - regex : not building - serialization : not building - signals : not building - system : not building - test : not building - thread : not building - timer : not building - wave : not building ...patience... ...found 690 targets... ...updating 51 targets... common.mkdir stage common.mkdir stage\lib common.mkdir C:\boost-filesystem\boost\bin.v2\libs common.mkdir C:\boost-filesystem\boost\bin.v2\libs\system common.mkdir C:\boost-filesystem\boost\bin.v2\libs\system\build common.mkdir C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0 common.mkdir C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\ debug common.mkdir C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\ debug\link-static common.mkdir C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\ debug\link-static\threading-multi gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1 .0\debug\link-static\threading-multi\error_code.o gcc.archive C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\d ebug\link-static\threading-multi\libboost_system-mgw51-mt-d-1_59.a common.copy stage\lib\libboost_system-mgw51-mt-d-1_59.a C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\debug\link-st atic\threading-multi\libboost_system-mgw51-mt-d-1_59.a 1 file(s) copied. common.mkdir C:\boost-filesystem\boost\bin.v2\libs\filesystem common.mkdir C:\boost-filesystem\boost\bin.v2\libs\filesystem\build common.mkdir C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5. 1.0 common.mkdir C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5. 1.0\debug common.mkdir C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5. 1.0\debug\link-static common.mkdir C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5. 1.0\debug\link-static\threading-multi gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\debug\link-static\threading-multi\codecvt_error_category.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\debug\link-static\threading-multi\operations.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\debug\link-static\threading-multi\path.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\debug\link-static\threading-multi\path_traits.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\debug\link-static\threading-multi\portability.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\debug\link-static\threading-multi\unique_path.o libs\filesystem\src\unique_path.cpp:28:0: warning: ignoring #pragma comment [-W unknown-pragmas] # pragma comment(lib, "Advapi32.lib") ^ gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\debug\link-static\threading-multi\utf8_codecvt_facet.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\debug\link-static\threading-multi\windows_file_codecvt.o gcc.archive C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5.1 .0\debug\link-static\threading-multi\libboost_filesystem-mgw51-mt-d-1_59.a common.copy stage\lib\libboost_filesystem-mgw51-mt-d-1_59.a C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5.1.0\debug\lin k-static\threading-multi\libboost_filesystem-mgw51-mt-d-1_59.a 1 file(s) copied. common.mkdir C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\ release common.mkdir C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\ release\link-static common.mkdir C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\ release\link-static\threading-multi gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1 .0\release\link-static\threading-multi\error_code.o In file included from libs\system\src\error_code.cpp:16:0: ./boost/system/error_code.hpp:221:36: warning: 'boost::system::posix_category' d efined but not used [-Wunused-variable] static const error_category & posix_category = generic_category(); ^ ./boost/system/error_code.hpp:222:36: warning: 'boost::system::errno_ecat' defin ed but not used [-Wunused-variable] static const error_category & errno_ecat = generic_category(); ^ ./boost/system/error_code.hpp:223:36: warning: 'boost::system::native_ecat' defi ned but not used [-Wunused-variable] static const error_category & native_ecat = system_category(); ^ gcc.archive C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\r elease\link-static\threading-multi\libboost_system-mgw51-mt-1_59.a common.copy stage\lib\libboost_system-mgw51-mt-1_59.a C:\boost-filesystem\boost\bin.v2\libs\system\build\gcc-mingw-5.1.0\release\link- static\threading-multi\libboost_system-mgw51-mt-1_59.a 1 file(s) copied. common.mkdir C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5. 1.0\release common.mkdir C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5. 1.0\release\link-static common.mkdir C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5. 1.0\release\link-static\threading-multi gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\release\link-static\threading-multi\codecvt_error_category.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\release\link-static\threading-multi\operations.o libs\filesystem\src\operations.cpp:688:26: warning: '{anonymous}::create_symboli c_link_api' defined but not used [-Wunused-variable] PtrCreateSymbolicLinkW create_symbolic_link_api = PtrCreateSymbolicLinkW( ^ gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\release\link-static\threading-multi\path.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\release\link-static\threading-multi\path_traits.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\release\link-static\threading-multi\portability.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\release\link-static\threading-multi\unique_path.o libs\filesystem\src\unique_path.cpp:28:0: warning: ignoring #pragma comment [-W unknown-pragmas] # pragma comment(lib, "Advapi32.lib") ^ gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\release\link-static\threading-multi\utf8_codecvt_facet.o gcc.compile.c++ C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw -5.1.0\release\link-static\threading-multi\windows_file_codecvt.o gcc.archive C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5.1 .0\release\link-static\threading-multi\libboost_filesystem-mgw51-mt-1_59.a common.copy stage\lib\libboost_filesystem-mgw51-mt-1_59.a C:\boost-filesystem\boost\bin.v2\libs\filesystem\build\gcc-mingw-5.1.0\release\l ink-static\threading-multi\libboost_filesystem-mgw51-mt-1_59.a 1 file(s) copied. ...updated 51 targets... So there are some warning while Bootstrapping the build engine, errors and failed targets when building the filesystem library. Should I be worried about them? What should I do?

1 0

Program Options and Filesystem ifstream
by Scott Morgan 19 Aug '15

19 Aug '15

Having a problem getting the following to compile under a Linux system (Mint 17.2, boost 1.54). It works okay with MSVC2010 and boost 1.57 though. **begin: main.cpp** #include <boost/filesystem/fstream.hpp> namespace fs = boost::filesystem; #include <boost/program_options.hpp> namespace po = boost::program_options; void test(fs::path& cfg_path, po::options_description& cfg_desc, po::variables_map& options) { po::store(po::parse_config_file(fs::ifstream(cfg_path), cfg_desc, true), options); } **end: main.cpp** Is this just a problem with 1.54's version of filesystem and/or program options? Scott **begin: GCC output** main.cpp: In function ‘void test(boost::filesystem::path&, boost::program_options::options_description&, boost::program_options::variables_map&)’: main.cpp:8:72: error: no matching function for call to ‘parse_config_file(boost::filesystem::ifstream, boost::program_options::options_description&, bool)’ po::store(po::parse_config_file(fs::ifstream(cfg_path), cfg_desc, true), options); ^ main.cpp:8:72: note: candidates are: In file included from /usr/include/boost/program_options.hpp:17:0, from main.cpp:3: /usr/include/boost/program_options/parsers.hpp:185:5: note: boost::program_options::basic_parsed_options<charT> boost::program_options::parse_config_file(std::basic_istream<charT>&, const boost::program_options::options_description&, bool) [with charT = char] parse_config_file(std::basic_istream<charT>&, const options_description&, ^ /usr/include/boost/program_options/parsers.hpp:185:5: note: no known conversion for argument 1 from ‘boost::filesystem::ifstream {aka boost::filesystem::basic_ifstream<char>}’ to ‘std::basic_istream<char>&’ /usr/include/boost/program_options/parsers.hpp:198:5: note: template<class charT> boost::program_options::basic_parsed_options<charT> boost::program_options::parse_config_file(const char*, const boost::program_options::options_description&, bool) parse_config_file(const char* filename, const options_description&, ^ /usr/include/boost/program_options/parsers.hpp:198:5: note: template argument deduction/substitution failed: main.cpp:8:72: note: cannot convert ‘boost::filesystem::basic_ifstream<char>((*(const boost::filesystem::path*)cfg_path))’ (type ‘boost::filesystem::ifstream {aka boost::filesystem::basic_ifstream<char>}’) to type ‘const char*’ po::store(po::parse_config_file(fs::ifstream(cfg_path), cfg_desc, true), options); ^ **end: GCC output**

2 3

multi_index member key extractors crash MSVC 2015
by Filip Konvička 19 Aug '15

19 Aug '15

Hi, it looks like using boost::multi_index::member<> crashes MSVC 2015 RTM when a const-qualified type is passed to it as the 2nd argument, but the member is actually non-const. #include <boost\multi_index_container.hpp> #include <boost\multi_index\member.hpp> #include <boost\multi_index\indexed_by.hpp> #include <boost\multi_index\ordered_index.hpp> struct X { int number; // non-const }; using namespace boost::multi_index; int main() { typedef multi_index_container<X, indexed_by<ordered_unique<member<X, const int, &X::number> > > > C; C c; c.find(1); // C1001 return 0; } ...\include\boost\multi_index\member.hpp(65): fatal error C1001: An internal error has occurred in the compiler. (compiler file 'f:\dd\vctools\compiler\utc\src\p2\main.c', line 246) I found the following on a related subject, but I'm not sure whether this is a separate issue or not. http://www.boost.org/development/tests/master/developer/output/teeks99-08l-… https://connect.microsoft.com/VisualStudio/feedback/details/1577162/vc-inte… https://groups.google.com/forum/#!topic/boost-devel-archive/gi-xGnCkvPI Thanks, Filip

2 1

[Asio] Measuring and improving SSL servier scalability
by Konrad Zemek 18 Aug '15

18 Aug '15

Hi all, I've built a few different Asio-based SSL servers in my career, but in my recent project the performance and resource-efficiency was paramount (as it's a library project), so I benchmarked it to make sure. Long story short, when benchmarking I found out that OpenSSL's error handling is a *very* serious bottleneck when scaling Asio+SSL over multiple threads. This can be "fixed", e.g. by using BoringSSL instead of OpenSSL, as BoringSSL uses thread-local storage for error data instead of locking a global mutex. As I didn't find any resources discussing bad Asio+SSL multithreaded performance (aside of one or two messages somewhere on this mailing list that complained about the problem; unfortunately I can't seem to find them right now), I've written up my knowledge into a blog post [1]. I believe it might be very useful to anyone who wants to build a multi-threaded SSL server/client on top of Asio. Konrad [1] https://konradzemek.com/2015/08/16/asio-ssl-and-scalability/

2 2