:) Jan, I think you said you'd help start the IP clearance bit?
On 15 May 2013 15:03, Noah Slater <nsla...@apache.org> wrote: > PARTY TIME 🎉 > > > On 15 May 2013 10:40, Robert Newson <rnew...@apache.org> wrote: > >> Thanks everyone. >> >> The tally is; >> >> 13 +1's >> >> The vote passes. We'll now move on to IP clearance. Once that's done >> the work will arrive on a feature branch in our main git repository. >> >> B. >> >> >> On 13 May 2013 04:31, Jason Smith <j...@iriscouch.com> wrote: >> > Sorry, just catching up. >> > >> > +1 >> > >> > On Fri, May 10, 2013 at 4:29 PM, Jan Lehnardt <j...@apache.org> wrote: >> >> +1 >> >> >> >> Jan >> >> -- >> >> >> >> On May 7, 2013, at 21:34 , Robert Newson <rnew...@apache.org> wrote: >> >> >> >>> Hi All, >> >>> >> >>> I propose to merge in the following work, >> >>> https://github.com/rnewson/couchdb/tree/nebraska-merge-candidate to >> >>> the official Apache CouchDB repository to a new branch (i.e, *not* >> >>> master). Once there, the full CouchDB developer community can begin >> >>> the work to incorporate the code here into an official release. >> >>> >> >>> You do not need to respond if you are in agreement. If there is no >> >>> response in 72 hours, I will assume lazy consensus. If we reach >> >>> consensus, I will start the IP clearance process and then the merge. >> >>> >> >>> As most of you know, Paul Davis and I recently sequestered ourselves >> >>> away from society (in a place called Nebraska) to make this merge >> >>> happen. I want to clarify that this work is not the BigCouch code you >> >>> can see on github.com/cloudant/bigcouch but the Cloudant platform from >> >>> which BigCouch was made. This means it is bang up to date with all the >> >>> bug fixes and feature enhancements we've made in the last eighteen >> >>> months or more. With that clarification made, here are our notes about >> >>> what we achieved, what it means to the project and what isn't yet >> >>> done; >> >>> >> >>> Nebraska Merge Roundup >> >>> >> >>> >> >>> Stats: >> >>> >> >>> >> >>> 1402 - total new commits >> >>> >> >>> 312 - commits written during the merge (will be reduced substantially >> >>> by squashing) >> >>> >> >>> 408 - number of files changed >> >>> >> >>> 21,897 - number of lines added >> >>> >> >>> 4,277 - number of lines removed >> >>> >> >>> A retrospective: >> >>> >> >>> Bob Newson and I have come to the end of our merge sprint on getting >> >>> BigCouch merged into Apache CouchDB. Its been a productive ten days >> >>> here in the midwest. I managed to get Bob out to a bowling alley and >> >>> he managed to get me to a sushi restaurant. In between the cultural >> >>> exchanges we’ve also managed to get a significant amount of work done >> >>> on the merging as well. >> >>> >> >>> >> >>> The current status of the merge is that we’ve managed to resolve the >> >>> differences in the single node execution of CouchDB. Both the >> >>> JavaScript and Erlang test suites run with only one failure in the >> >>> Erlang test suite due to a (deliberately) missing constraint on the >> >>> number of operating system processes. This should be a relatively >> >>> straightforward fix but was not prioritized during our limited time to >> >>> work on the larger issues. >> >>> >> >>> >> >>> We merged a large number of performance and stability enhancements >> >>> back into single node CouchDB as well as a number of pure bug fixes. >> >>> The biggest highlight is a brand new compactor that is both faster and >> >>> creates smaller and better organized post-compaction databases. >> >>> >> >>> >> >>> The current status of the merge is that single node operations should >> >>> be completely unaffected as demonstrated by the test suite passing. On >> >>> the other hand we haven’t yet finished getting the clustered code >> >>> merged to use some of the new changes in single node CouchDB. The >> >>> single most significant portion of this work involves updates to the >> >>> internal cluster API for views to use the recently rewritten indexer >> >>> APIs. This should be a relatively straightforward bit of work that >> >>> we’ll be finishing over the next few weeks. >> >>> >> >>> >> >>> All in all the merge work done so far has been quite successful. We’ve >> >>> met our primary goal of getting the code merged in a fashion that does >> >>> not affect single node operation while providing a starting point for >> >>> the larger community to start reviewing the more significant changes >> >>> made. Given the size of the diff between the two code bases we never >> >>> expected to have a fully working clustered solution after ten days of >> >>> work but we have succeeded in providing a base of work that will allow >> >>> us and new contributors to get up to speed quickly. >> >>> >> >>> >> >>> This work, coupled with work by Dave Cottlehuber and Benoît Chesneau >> >>> on updating the build system and various other internal updates, will >> >>> provide a solid foundation for work going forward. Its an exciting >> >>> time for CouchDB and anyone interested should keep an eye on the next >> >>> few releases as we ramp up work on various core aspects of the >> >>> database. >> >>> >> >>> >> >>> We’ve had an exciting few days working to prepare the road for an >> >>> exciting next twelve to eighteen months. We hope that everyone will >> >>> feel as excited as we do about the next twelve to eighteen months for >> >>> Apache CouchDB. It should be an exciting ride. >> >>> >> >>> >> >>> >> >>> Things we got done >> >>> >> >>> >> >>> * Large update to the source tree layout for Erlang applications. Each >> >>> application now has a src/appname/(c_src|ebin|priv|src) structure. The >> >>> build system has been updated. >> >>> >> >>> * Renamed src/couchdb to src/couch to match the Erlang convention of >> >>> the top directory name matching the Erlang application name. >> >>> >> >>> * Imported Cloudant Erlang applications for clustered CouchDB. These >> >>> are imported with their history by using git subtree and merging the >> >>> top level commit. These are not external deps, development will happen >> >>> within the CouchDB tree. The imported apps are: >> >>> >> >>> >> >>> * config - A couch_config replacement (Behavior is mostly identical >> >>> to couch_config except how we listen for configuration changes >> >>> internally to allow for smooth hot code upgrade). >> >>> >> >>> * twig - An rsyslog source replacement for couch_log. >> >>> >> >>> * rexi - An RPC library. Replaces Erlang’s built-in rex application >> >>> to avoid costly safety measures in the interest of performance and >> >>> throughput. >> >>> >> >>> * mem3 - The “Dynamo” part of BigCouch responsible for managing >> cluster state >> >>> >> >>> * fabric - The internal cluster-aware CouachDB API >> >>> >> >>> * ets_lru - A small library application that provides an LRU >> >>> implementation using a couple ets tables. >> >>> >> >>> * ddoc_cache - Caches design documents on each node for use in >> >>> design handler functions. This uses an ets_lru cache with a very short >> >>> TTL. >> >>> >> >>> * chttpd - The cluster aware HTTP layer >> >>> >> >>> >> >>> Each imported app also had its build system updated to use Autotools >> >>> along with the necessary updates noted above for the new application >> >>> layouts for existing CouchDB erlang apps. >> >>> >> >>> >> >>> * Merged a large amount of updates and fixes to couch_replicator based >> >>> on work done internally at Cloudant. Unfortunately due to an error >> >>> when we created our internal clone we lost a bit of history in some of >> >>> the initial merge and have a big commit that affects >> >>> couch_replicator_manager mostly. There are a number of other commits >> >>> related to couch_replicator that resolve the single node vs. clustered >> >>> differences. Some noticeable couch_replicator features: >> >>> >> >>> >> >>> * Optionally disable checkpoints so that replication can work when >> >>> a source is read only. This should only be used for smaller databases >> >>> as each replication call has to scan the entire source database on >> >>> each invocation. >> >>> >> >>> * A new changes_pending field in the _active_tasks output >> >>> >> >>> * A fix to the continuous replication to automatically reconnect to >> >>> a continuous changes feed when it sees a last_seq value. This allows >> >>> for the source to selectively recycle the HTTP connections used which >> >>> can be quite useful for “permanent” replications. >> >>> >> >>> * A multitude of smaller bug fix and stability enhancements. >> >>> >> >>> >> >>> Updates to single node couch: >> >>> >> >>> >> >>> * We changed the by_seq tree to store a copy of the #full_doc_info{} >> >>> record instead of the #doc_info{} record. This gives significant speed >> >>> improvements for compaction and replication and generally anything >> >>> that needs to walk the by_seq tree and access document bodies >> >>> internally. >> >>> >> >>> * We rewrote the compactor to be significantly faster as well as >> >>> provides significantly better compacted databases. The two main halves >> >>> are to use a temp file and replace the use of btrees in the temp file. >> >>> The temp file only contains a temporary copy of the document ids. At >> >>> the end of a compaction run we then rebuild the by_id btree in the >> >>> compaction file from this temp file. The reason this helps so much is >> >>> that the compaction is based on the update_seq btree, which for most >> >>> cases means that the id tree is updated in roughly random order which >> >>> is very bad for our append only btrees. By using the tmp file we can >> >>> stream it in order back into the compacted db file at the end of >> >>> compacting, generating a minimum amount of garbage in the process. The >> >>> other upgrade was to implement an external merge sort module >> >>> (couch_emsort) that is used with this temporary file. >> >>> >> >>> * Reject updates to design docs that introduce updates that break >> >>> compilation for source code. Currently we only check map and reduce >> >>> calls as the other should provide user visible errors instead of >> >>> inexplicably empty views. >> >>> >> >>> because my OCD kicked in and I was unable to resist. >> >>> >> >>> * Reverted a change made a long time ago that uses two file >> >>> descriptors for each database. See the todo list. >> >>> >> >>> * The reason to remove the second fd is so that we can rewrite ref >> >>> counting. Better ref counting makes everyone happy, but the real >> >>> reason is for this next bullet point: >> >>> >> >>> * Optimize couch_server to not require a round trip message pass for >> >>> opening a database that’s in the LRU. This is a significant >> >>> performance boost for high concurrency access. We also optimized >> >>> couch_server internals to not blow up when it’s under load. >> >>> >> >>> * Introduce a #leaf{} record into the revision trees. This is never >> >>> written to disk but makes internal code a lot cleaner when dealing >> >>> with multiple versions of rev tree values. >> >>> >> >>> * Some changes to couch_changes to enable clustered access. Also some >> >>> general cleanup >> >>> >> >>> * Internal changes to how CouchDB is booted in Erlang land. Not very >> >>> sexy but this removes a lot of complicated un-Erlangy bits. We still >> >>> have a bit of work left here. >> >>> >> >>> * btree chunk sizes are now configurable which can allow people to >> >>> adjust the RAM/speed tradeoffs a bit more. >> >>> >> >>> * We now load update validation functions on the first write. This is >> >>> a cluster-motivated change because the clustered version of this call >> >>> is expensive and can lead to race conditions when opening a bunch of >> >>> db shards simultaneously. This should be invisible to external >> >>> clients. >> >>> >> >>> * Disabled conflict detection for local docs. They don’t replicate so >> >>> there’s no point. This just led to clusters getting stuck and confused >> >>> when there were lots of replications happening. >> >>> >> >>> * Changes to the multipart/mime parsing code. Necessary for clustered >> >>> attachment uploads to split the incoming data stream into N copies. >> >>> >> >>> * Don’t use init:restart/0 when reloading the ICU driver. I think >> >>> this has a bug. But we should rewrite this driver to be a NIF anyway. >> >>> >> >>> * New couch OS process manager. Significantly faster access to OS >> >>> processes under heavy load. This replaces the hard limit with a soft >> >>> limit. Process spawned over the soft limit will be used until they’ve >> >>> sat idle for a few minutes and then be closed. We have a todo item to >> >>> add the hard ceiling back in (while keeping the soft ceiling). >> >>> >> >>> * Automatically replace some easily identifiable JS reductions with >> >>> their builtin counterparts. Uses a regex to do the detection so its >> >>> not too smart. >> >>> >> >>> * Improved view updater write batch. >> >>> >> >>> * Updates to couchjs’ views.js to improve index update speeds >> >>> >> >>> * Updates to the _stats bultin reduce to allow reduces to work over >> >>> emitted stats objects. Sometimes clients have summary data in a doc, >> >>> and this allows them to combine stats if they follow the same pattern >> >>> as the builtin expects. >> >>> >> >>> * Added a config:reload() that is accessible by POST’ing to >> >>> _config/_reload. Used by the JS tests to reset the config to what's on >> >>> disk. This should prevent those test run failures where a test fails >> >>> leaving the config in a bad state causing all subsequent tests to >> >>> fail. I think. Maybe. >> >>> >> >>> * Databases are deleted synchronously in the test suite. We may need >> >>> to address this on Windows. But it does seem to reduce the number of >> >>> “{error, file_exists}” failures. >> >>> >> >>> * I reimplemented the JS restartServer() function. There’s a new >> >>> _restart/token URL that will given a unique value for each instance of >> >>> the Erlang VM. To run a restart we grab the current token value, hit >> >>> _restart, then wait till we get a successful response with a different >> >>> token. This appears to have made the restart strategy more robust. >> >>> >> >>> >> >>> >> >>> Things that need doing >> >>> >> >>> >> >>> IP Clearance - >> >>> >> >>> >> >>> We’ll need to track down if we have the CCLA as well as look at each >> >>> source file added to make sure each one is strictly from Cloudant or >> >>> has an amenable license. I’m pretty sure that the only one of interest >> >>> is trunc_io.erl but we need to be thorough. >> >>> >> >>> documentation - >> >>> >> >>> >> >>> There shouldn’t be much here since the entire point of this merge was >> >>> to not change the visible behavior of single node couch. A few things >> >>> to add about the testing endpoints. Maybe an update to the compaction >> >>> section mention the two new file names used. >> >>> >> >>> >> >>> Copyright notices - >> >>> >> >>> >> >>> We need to strip out copyright notices from individual files and make >> >>> sure all files have a standard Apache License v2 header. >> >>> >> >>> >> >>> clustered vhosts - >> >>> >> >>> >> >>> We’ve never implemented this at Cloudant. We either need to write a >> >>> cluster or go back and tell people to use HAProxy (or similar) for >> >>> such things. >> >>> >> >>> >> >>> twig - >> >>> >> >>> >> >>> We need to add another output type to twig that is configurable in >> >>> some manner. Right now we spit out entire rsyslog records which isn’t >> >>> useful for most people. We’ll need to implement the file writer from >> >>> couch_log as well as update the _log HTTP handler to know when it can >> >>> and can’t expect to find data on disk. >> >>> >> >>> >> >>> fabric - >> >>> >> >>> >> >>> This is going to need a lot of work. Specifically view access is going >> >>> to need to be updated to work with couch_mrview and friends. >> >>> >> >>> >> >>> Boot a dev cluster - >> >>> >> >>> >> >>> Once we fix up the clustering code we’ll need to write instructions >> >>> and scripts for pulling up a dev cluster. >> >>> >> >>> >> >>> OTP stuff - >> >>> >> >>> >> >>> We’ve updated each app but we still need to pull some parts out of >> >>> couchdb into their own application. Specifically the HTTP layer needs >> >>> its own app. We could probably pull out the os process/query_servers >> >>> as well as the os daemons and friends. Once done we need to update the >> >>> supervision trees so we don’t have things like couch starting and >> >>> managing the replication manager process. >> >>> >> >>> >> >>> ddoc_cache - >> >>> >> >>> >> >>> Wire this up in couch_httpd_db to actually be used. Right now its only >> >>> used in chttpd. >> >>> >> >>> >> >>> couch_file upgrade - >> >>> >> >>> >> >>> The revert to remove the second updater_fd from each #db{} record >> >>> means that we’re back in the original position of files appearing to >> >>> slow down significantly under load. Since the initial hammer approach >> >>> of just adding a second fd we’ve since discovered that the underlying >> >>> bug is due to the way that message passing works combined with >> >>> Erlang’s file io. Significantly though is the fact that the fix is >> >>> rather simple to implement. A first draft of this work is on an old >> >>> branch of mine here: >> >>> >> >>> >> >>> https://github.com/davisp/couchdb/commit/d856878 >> >>> >> >>> >> >>> finish the size calculating changes - >> >>> >> >>> >> >>> The #leaf{} record change is to enable us to add more data size >> >>> calculations. CouchDB master calculates a data size that account for >> >>> all bytes that are active in a .couch file. Cloudant is interested in >> >>> the total size of uncompressed docs and attachments minus the internal >> >>> overhead of btrees. And there’s a fourth number to calculate based on >> >>> the compression level used. Having each of these numbers will be >> >>> useful as well as the calculations they’ll enable (ie, dead bytes in >> >>> file, bytes used for overhead, compression ratio achieved, etc). >> >>> >> >>> >> >>> couch_proc_manager - >> >>> >> >>> >> >>> We need to implement the hard ceiling for capping the number of OS >> >>> processes. We’ve started seeing a need for this at Cloudant with some >> >>> work loads so motivation to fix this is high. The only failing etap is >> >>> the assertion of this ceiling. >> >>> >> >>> >> >>> Synchronous db delete on Windows - >> >>> >> >>> >> >>> I did this because running the test suite was driving me bonkers. I >> >>> need to ask Dave about how this behaves on Windows (my guess is not >> >>> well) but I think we can close things up so that it works better than >> >>> the status quo. >> >> >> > >> > >> > >> > -- >> > Iris Couch >> > > > > -- > NS
