Is the expected overhead something like this: # rolling upgrade of system with configs in place that disable tracing # upgrade tracing service # rolling restart of system with configs in place to re-enable tracing
An extra rolling restart just due to tracing does seem like a large request. Does the tracing RPC have enough primitives that we could implement a versioned handshake? On Sun, Feb 21, 2016 at 10:10 PM, Stack <[email protected]> wrote: > "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 > > >> > > > -- Sean
