"The rationale for this limitation is that tracing can simply be disabled for a brief period during the rolling upgrade process."
The second time an operator has to do this, they'll just throw away tracing as a PITA. Tracing needs to bend to serve the traced systems, not the other way around. A 4.0.1 can't talk to a 4.1.0? Do you know how it is broken? St.Ack On Fri, Feb 19, 2016 at 5:17 PM, Colin P. McCabe <[email protected]> wrote: > Our compatibility policy (see > > http://mail-archives.apache.org/mod_mbox/htrace-dev/201509.mbox/%[email protected]%3E > ) only covers the htrace-core4 API right now. So we can guarantee > that any projects using htrace-core 4.0.1 can upgrade to htrace-core > 4.1.0 without breaking anything. (This is a more painful guarantee > than it sounds since it means we can't remove functions, only > deprecate them... And so forth.) But it's a very useful guarantee > for our downstream projects. > > However, we don't support mixing and matching versions of the > SpanReceiver client and server components. The admin has to roll out > a uniform version of those components-- for example, using htraced > 4.0.1 with htrace-htraced.jar 4.1.0 is not supported. The rationale > for this limitation is that tracing can simply be disabled for a brief > period during the rolling upgrade process. Also, the different > SpanReceiver subprojects are at different levels of maturity, and > imposing heavy compatibility guarantees would slow down development > for no real gain. > > best, > Colin > > > On Fri, Feb 19, 2016 at 4:32 PM, Stack <[email protected]> wrote: > > Can a 4.0.1 client talk to a 4.1.0 htrace? Has it been tested? > > St.Ack > > > > On Tue, Feb 9, 2016 at 7:00 PM, Colin P. McCabe <[email protected]> > wrote: > > > >> Hi all, > >> > >> I've posted the second release candidate for HTrace 4.1 here: > >> > >> http://people.apache.org/~cmccabe/htrace/releases/4.1.0/rc2/ > >> > >> The jars have been staged here: > >> > >> https://repository.apache.org/content/repositories/orgapachehtrace-1022 > >> > >> Compared to rc1, this rc includes HTRACE-334 and HTRACE-342. > >> > >> HTrace 4.1 brings a lot of robustness improvements. There were major > >> improvements to htraced and the web UI, as well as new metrics added. > >> There were numerous build fixups, and we added Docker support, to > >> ensure a repeatable build. > >> > >> Check it out. The vote will run for 5 days. > >> > >> cheers, > >> Colin > >> > >> > >> Release Notes - HTrace - Version 4.1 > >> ** Bug > >> * [HTRACE-114] - Fix compilation error of htrace-hbase against > >> hbase-1.0.0 > >> * [HTRACE-238] - Change maven compiler source level to 1.7 to > >> match targetJdk > >> * [HTRACE-243] - Remove duplicate maven-assembly-plugin > >> configuration section in htrace-htraced/pom.xml > >> * [HTRACE-245] - NOTICE.txt: change "developed by The Apache > >> Software...” to "developed at The Apache Software...” > >> * [HTRACE-246] - HTrace WebApp not properly defined and therefore > >> not packaged into .war > >> * [HTRACE-248] - HTraced should gracefully shutdown if stopped > >> * [HTRACE-249] - Script and doc on how to publish website > >> * [HTRACE-251] - Fix "mvn clean" target > >> * [HTRACE-253] - Tracer loadSamplers and loadSpanReceivers logs > >> are too chatty > >> * [HTRACE-256] - Change the artifactId for htrace-core in branch > >> 4.0 to be htrace-core4 > >> * [HTRACE-257] - htrace-htraced: add web symlink rather than > >> generating programmatically > >> * [HTRACE-262] - Temporarily suppress doclint for Java 8 to > >> prevent build failure > >> * [HTRACE-266] - Make the CLIENT_REST_MAX_SPANS_AT_A_TIME_KEY > >> config key more consistent with other configs > >> * [HTRACE-267] - Move owl logo licensing information from NOTICE to > >> LICENSE > >> * [HTRACE-268] - Remove Units and go-codec from LICENSE since they > >> are not contained in the source release > >> * [HTRACE-272] - TracerPool must not load multiple inscance of > >> same receiver class when a simple classname is given > >> * [HTRACE-279] - Fix issues where the HTracedSpanReceiver was > >> using the wrong JSON serialization for spans and add validation to > >> htraced REST ingest path > >> * [HTRACE-280] - htraced: add metrics about total spans added and > >> dropped per address > >> * [HTRACE-281] - htraced: add example/htraced-conf.xml > >> * [HTRACE-282] - htraced: reap spans which are older than a > >> configurable interval > >> * [HTRACE-283] - Heartbeater should wait for goroutine to finish on > >> close > >> * [HTRACE-284] - htrace-htraced, htrace-flume: do not treat the > >> shaded version of commons-logging as provided > >> * [HTRACE-285] - htraced tool: fix query parsing and add query_test > >> * [HTRACE-289] - Fix TraceEnabled, etc. logger methods for > >> conditional logging > >> * [HTRACE-294] - htraced: fix some metrics issues > >> * [HTRACE-297] - htraced: avoid serializing spans to json unless > >> TRACE logging is enabled > >> * [HTRACE-300] - Reaper should be initialized before shards are > >> activated > >> * [HTRACE-301] - htraced: fix unit tests that aren't waiting for > >> spans to be written, use semaphore for WrittenSpans > >> * [HTRACE-302] - htraced: Add admissions control to HRPC to limit > >> the number of incoming messages > >> * [HTRACE-304] - htraced: fix bug with GREATER_THAN queries > >> * [HTRACE-307] - htraced: queries sometimes return no results even > >> when many results exist due to confusion in iterator usage > >> * [HTRACE-311] - htraced: Fix logging to stdout via -Dlog.path= > >> * [HTRACE-316] - htrace-web: span.js issue: span ID string length > >> is 32, not 36 > >> * [HTRACE-317] - Fix the documentation for adding tracing to an > >> application to reflect HTrace 4.x API changes > >> * [HTRACE-328] - htraced continues scanning in some cases even > >> when no more results are possible > >> > >> ** Improvement > >> * [HTRACE-342] - centralize building instructions in BUILDING.txt > >> * [HTRACE-334] - htrace-web: Make limit of search and children API > >> configurable > >> * [HTRACE-129] - htraced: add /server/stats REST endpoint > >> * [HTRACE-156] - HTrace GUI: add about view > >> * [HTRACE-181] - gui: Split "about" screen > >> * [HTRACE-237] - Optimize htraced span receiver > >> * [HTRACE-239] - Add htrace/impl/TestZipkinSpanReceiver.java > >> * [HTRACE-260] - htrace-zipkin should not set the obsolete > >> duration field in thrift > >> * [HTRACE-271] - Add log4j.properties to all submodule tests > >> * [HTRACE-276] - Shade classes into org.apache.htrace.shaded > >> rather than org.apache.htrace > >> * [HTRACE-286] - htraced: improvements to logging, daemon startup, > >> and configuration > >> * [HTRACE-290] - htraced: Fix per-faculty log level settings and > >> add unit tests for conditional logging > >> * [HTRACE-291] - rename bin/htrace to bin/htracedTool > >> * [HTRACE-292] - "htracedTool version" should display the git > >> hash, and -Dgit.version option should be available for build > >> * [HTRACE-295] - htraced: setting span.expiry.ms to 0 should > >> disable span expiry > >> * [HTRACE-296] - htraced tests: make sure local settings for > >> HTRACED_WEB_DIR and HTRACE_CONF_DIR don't affect unit tests > >> * [HTRACE-298] - htraced: improve datastore serialization and > metrics > >> * [HTRACE-303] - Add client-side htraceDropped log file to track > >> dropped spans > >> * [HTRACE-305] - htrace-web: Use greater-than-or-equal rather than > >> greater-than in more places > >> * [HTRACE-306] - htraced: logs should use UTC > >> * [HTRACE-308] - Deserialize WriteSpans requests incrementally > >> rather than all at once to optimize GC > >> * [HTRACE-310] - htracedTool: when there is an error response, > >> print the body of the response > >> * [HTRACE-312] - htraced: if GOMAXPROCS is left at 1, set it to > >> the number of CPUs > >> * [HTRACE-313] - htraced span receiver clientDropped file should > >> include timestamps > >> * [HTRACE-314] - htraced: make datastore loading safer > >> * [HTRACE-327] - HTRACE-327: improve htraced command-line parsing > >> and add version command > >> * [HTRACE-334] - htrace-web: Make limit of search and children API > >> configurable > >> * [HTRACE-335] - htrace-web: Adjust size of span widget > >> * [HTRACE-339] - Major type in htrace-flume README > >> > >> ** New Feature > >> * [HTRACE-235] - htrace-zipkin - add Kafka transport support > >> * [HTRACE-277] - htraced: Add /server/conf endpoint to get server > >> configuration > >> * [HTRACE-278] - htraced: dump thread stacks and GC statistics > >> when SIGQUIT is sent > >> * [HTRACE-288] - htraced: Add a user interface to view server > >> version, metrics, and configuration > >> * [HTRACE-293] - htrace-web: control-click should fully expand trace > >> trees > >> * [HTRACE-299] - htraced: add /server/debugInfo REST endpoint to > >> get stack traces and GC stats > >> * [HTRACE-309] - htraced: improve leveldb configuration > >> * [HTRACE-323] - htrace-web: change the cursor to a spinner while > >> a search is in progress > >> * [HTRACE-332] - htraced: optionally enable leveldb LRU cache > >> > >> ** Task > >> * [HTRACE-241] - Docker image for HTrace > >> * [HTRACE-315] - htraced: change default web port from 9095 to 9096 > >> * [HTRACE-319] - mark versions 4.0 and 4.0.1 as released > >> * [HTRACE-331] - create git tags for 4.0 and 4.0.1 releases > >> > >> ** Wish > >> * [HTRACE-269] - HTraceConfiguration support to get the map of > >> configurations > >> >
