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[Maria-developers] Transactions behind a failed transaction could commit in parallel replication
by nanyi607rao 21 Mar '14

21 Mar '14

hi kristian, In parallel replication if a transaction executed failed, replication should stop immediately(unconsider retry), and transactions behind the failed one should skip or rollback. you did try to do like this, there are codes like: if (unlikely(entry->stop_on_error_sub_id <= rgi->wait_commit_sub_id)) skip_event_group= true; this codes can tell latter transactions to skip but can't tell them rollback. because if a transaction started commiting before a … [View More]

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Re: [Maria-developers] MDEV-5914
by Kristian Nielsen 21 Mar '14

21 Mar '14

Jan Lindström <jplindst(a)mariadb.org> writes: > Here is necessary changes. I have run whole mysql-test-run and I did not see > any failures, thus is is mostly safe. I say mostly, > because we really do not have much test cases that would use multimaster setup > and try to get conflicting transactions > generated from local clients against slave thread. Thanks a lot! I will try to come up with some test cases for this, with replication and external transactions that … [View More]conflict and show the problem. In parallel, I tried running the parallel replication slaves with READ COMMITTED; that also seems to work and can get Elena able to continue testing. But this change is potentially more correct; I will let you know when I have some test results. - Kristian. > ================================= > > jan@jan-GE70-0NC-0ND ~/mysql/10.0-mdev5914 $ bzr diff > === modified file 'include/mysql/plugin.h' > --- include/mysql/plugin.h 2014-02-26 14:28:07 +0000 > +++ include/mysql/plugin.h 2014-03-21 09:05:58 +0000 > @@ -617,6 +617,7 @@ > int thd_in_lock_tables(const MYSQL_THD thd); > int thd_tablespace_op(const MYSQL_THD thd); > long long thd_test_options(const MYSQL_THD thd, long long test_options); > +unsigned long long thd_group_commit_id(const MYSQL_THD thd); > int thd_sql_command(const MYSQL_THD thd); > void **thd_ha_data(const MYSQL_THD thd, const struct handlerton *hton); > void thd_storage_lock_wait(MYSQL_THD thd, long long value); > > === modified file 'include/mysql/plugin_audit.h.pp' > --- include/mysql/plugin_audit.h.pp 2013-12-22 16:11:20 +0000 > +++ include/mysql/plugin_audit.h.pp 2014-03-21 09:06:17 +0000 > @@ -298,6 +298,7 @@ > int thd_in_lock_tables(const void* thd); > int thd_tablespace_op(const void* thd); > long long thd_test_options(const void* thd, long long test_options); > +unsigned long long thd_group_commit_id(const void* thd); > int thd_sql_command(const void* thd); > void **thd_ha_data(const void* thd, const struct handlerton *hton); > void thd_storage_lock_wait(void* thd, long long value); > > === modified file 'include/mysql/plugin_auth.h.pp' > --- include/mysql/plugin_auth.h.pp 2013-12-22 16:11:20 +0000 > +++ include/mysql/plugin_auth.h.pp 2014-03-21 09:06:35 +0000 > @@ -298,6 +298,7 @@ > int thd_in_lock_tables(const void* thd); > int thd_tablespace_op(const void* thd); > long long thd_test_options(const void* thd, long long test_options); > +unsigned long long thd_group_commit_id(const void* thd); > int thd_sql_command(const void* thd); > void **thd_ha_data(const void* thd, const struct handlerton *hton); > void thd_storage_lock_wait(void* thd, long long value); > > === modified file 'include/mysql/plugin_ftparser.h.pp' > --- include/mysql/plugin_ftparser.h.pp 2013-12-22 16:11:20 +0000 > +++ include/mysql/plugin_ftparser.h.pp 2014-03-21 09:06:59 +0000 > @@ -251,6 +251,7 @@ > int thd_in_lock_tables(const void* thd); > int thd_tablespace_op(const void* thd); > long long thd_test_options(const void* thd, long long test_options); > +unsigned long long thd_group_commit_id(const void* thd); > int thd_sql_command(const void* thd); > void **thd_ha_data(const void* thd, const struct handlerton *hton); > void thd_storage_lock_wait(void* thd, long long value); > > === modified file 'sql/sql_class.cc' > --- sql/sql_class.cc 2014-03-20 14:36:45 +0000 > +++ sql/sql_class.cc 2014-03-21 09:07:12 +0000 > @@ -675,6 +675,12 @@ > } > > extern "C" > +unsigned long long thd_group_commit_id(const THD *thd) > +{ > + return thd->rpl_group_commit_id; > +} > + > +extern "C" > int thd_sql_command(const THD *thd) > { > return (int) thd->lex->sql_command; > > === modified file 'storage/innobase/handler/ha_innodb.cc' > --- storage/innobase/handler/ha_innodb.cc 2014-02-26 18:36:33 +0000 > +++ storage/innobase/handler/ha_innodb.cc 2014-03-20 15:42:27 +0000 > @@ -2048,6 +2048,8 @@ > trx->check_unique_secondary = !thd_test_options( > thd, OPTION_RELAXED_UNIQUE_CHECKS); > > + trx->group_commit_id = thd_group_commit_id(thd); > + > DBUG_VOID_RETURN; > } > > > === modified file 'storage/innobase/include/trx0trx.h' > --- storage/innobase/include/trx0trx.h 2014-02-26 18:36:33 +0000 > +++ storage/innobase/include/trx0trx.h 2014-03-20 15:28:19 +0000 > @@ -840,6 +840,7 @@ > or the state last time became > TRX_STATE_ACTIVE */ > trx_id_t id; /*!< transaction id */ > + ib_uint64_t group_commit_id;/*!< Group commit id or 0 */ > XID xid; /*!< X/Open XA transaction > identification to identify a > transaction branch */ > > === modified file 'storage/innobase/lock/lock0lock.cc' > --- storage/innobase/lock/lock0lock.cc 2014-02-26 18:22:48 +0000 > +++ storage/innobase/lock/lock0lock.cc 2014-03-21 09:32:54 +0000 > @@ -1020,6 +1020,23 @@ > return(FALSE); > } > > + if (trx->group_commit_id != 0 && > + lock2->trx->group_commit_id != 0 && > + trx->group_commit_id == lock2->trx->group_commit_id && > + (type_mode & LOCK_GAP || lock_rec_get_gap(lock2))) { > + /* No lock request needs to wait GAP locks if > + transactions belong to the same group commit group. > + This is because we have already verified these > + transactions on master that they do not conflict > + on record locks but as they could be executed on > + different order on slave we should not wait for > + gap locks here. Note that parallel replication > + makes sure that transaction commits are executed > + in the same order in master and slave. */ > + > + return (FALSE); > + } > + > return(TRUE); > } > > > === modified file 'storage/xtradb/handler/ha_innodb.cc' > --- storage/xtradb/handler/ha_innodb.cc 2014-02-26 18:21:23 +0000 > +++ storage/xtradb/handler/ha_innodb.cc 2014-03-20 15:42:41 +0000 > @@ -2308,6 +2308,8 @@ > > trx->fake_changes = THDVAR(thd, fake_changes); > > + trx->group_commit_id = thd_group_commit_id(thd); > + > #ifdef EXTENDED_SLOWLOG > if (thd_log_slow_verbosity(thd) & (1ULL << SLOG_V_INNODB)) { > trx->take_stats = TRUE; > > === modified file 'storage/xtradb/include/trx0trx.h' > --- storage/xtradb/include/trx0trx.h 2014-02-26 18:21:23 +0000 > +++ storage/xtradb/include/trx0trx.h 2014-03-20 15:28:20 +0000 > @@ -861,6 +861,7 @@ > or the state last time became > TRX_STATE_ACTIVE */ > trx_id_t id; /*!< transaction id */ > + ib_uint64_t group_commit_id;/*!< Group commit id or 0 */ > XID xid; /*!< X/Open XA transaction > identification to identify a > transaction branch */ > > === modified file 'storage/xtradb/lock/lock0lock.cc' > --- storage/xtradb/lock/lock0lock.cc 2013-12-22 16:06:50 +0000 > +++ storage/xtradb/lock/lock0lock.cc 2014-03-21 09:32:46 +0000 > @@ -1021,6 +1021,23 @@ > return(FALSE); > } > > + if (trx->group_commit_id != 0 && > + lock2->trx->group_commit_id != 0 && > + trx->group_commit_id == lock2->trx->group_commit_id && > + (type_mode & LOCK_GAP || lock_rec_get_gap(lock2))) { > + /* No lock request needs to wait GAP locks if > + transactions belong to the same group commit group. > + This is because we have already verified these > + transactions on master that they do not conflict > + on record locks but as they could be executed on > + different order on slave we should not wait for > + gap locks here. Note that parallel replication > + makes sure that transaction commits are executed > + in the same order in master and slave. */ > + > + return (FALSE); > + } > + > return(TRUE); > } [View Less]

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[Maria-developers] [GSoC 2014] CREATE OR REPLACE, CREATE IF NOT EXISTS and DROP IF EXISTS
by sriram patil 21 Mar '14

21 Mar '14

Hi Sergei, I just went through WL#3129 (thanks to James Briggs for the link). It gave me a detailed insight on what exactly is expected. I have missed 2 object types in my proposal which are, USER and SERVER. I can edit my proposal to incorporate the changes in the deliverables timeline if you want me to. Thanks, Sriram

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Re: [Maria-developers] [GSOC 2014] "CREATE OR REPLACE, CREATE IF NOT EXISTS, and DROP IF EXISTS" Project
by Sergei Golubchik 21 Mar '14

21 Mar '14

Hi, Sriram! First: please don't forget to cc: the list maria-developers(a)lists.launchpad.net Thank you. On Mar 18, sriram patil wrote: > Hi Sergei, > > I was going through the source code and was able to figure out the > flow of query execution and major functions through which a query goes > before execution. > > The query execution majorly dwells in the "sql" directory of the > source code. So, I think I will have to make changes in the following > files … [View More]

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[Maria-developers] [GSoC] MDEV-371- index on BLOB
by smit hinsu 21 Mar '14

21 Mar '14

Hi Sergei and Roberto, My name is Smit Hinsu and I am final year undergrad student. I have good knowledge about database internals and good experience with C++. I find feature of creating index on BLOB quickly using MD-5 interesting. I have understood basic requirements for this feature. I have following questions in my mind currently. I think, HASH index is not supported in MySQL's version of MyISAM storage engine. Has MariaDB removed this restriction? We should support index for BLOB for … [View More]

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[Maria-developers] Engine independent index statistics - infrastructure questions
by Sergey Petrunia 20 Mar '14

20 Mar '14

Hello Igor and others, I've been playing around with engine independent statistics, and got a few questions. == mysqldump == mysqldump dumps table' data, but besides that it can dump other related objects, e.g. it will dump triggers that are attached to the table. Should it dump table statistics values, also? This question is of interest for DBAs, but also for optimizer developers. If a user has a complaint about the optimizer, we frequently ask them to upload a dataset. How do we request … [View More]

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[Maria-developers] [GSoC 2014]
by Ivan Nikulin 20 Mar '14

20 Mar '14

Hello, I would like to take part into one of your projects on base of GSoC 2014. I am an experienced C/C++ programmer with wide knowledge of algorithms and data structures and huge interest into this sphere. I have some basic knowledge of SQL language, but unfortunatelly I don't have any database development experience. Nevertheless, gaining the latter is my essential purpose. Can I count on a chance of taking part in one of your projects? Sorry for writing to you that late. P.S. I tried … [View More]

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Re: [Maria-developers] [Commits] Rev 4053: MDEV-5864 - Reduce usage of LOCK_open: TABLE_SHARE::tdc.free_tables
by Sergei Golubchik 19 Mar '14

19 Mar '14

Hi, Sergey! On Mar 15, Sergey Vojtovich wrote: > At lp:maria/10.0 > > ------------------------------------------------------------ > revno: 4053 > revision-id: svoj(a)mariadb.org-20140315185301-ce4r6br023co80dm > parent: sanja(a)montyprogram.com-20140314073116-nklb0jkjd4t1w40n > committer: Sergey Vojtovich <svoj(a)mariadb.org> > branch nick: 10.0 > timestamp: Sat 2014-03-15 22:53:01 +0400 > message: > MDEV-5864 - Reduce usage of LOCK_open: TABLE_SHARE::… [View More]tdc.free_tables > > Let TABLE_SHARE::tdc.free_tables, TABLE_SHARE::tdc.all_tables, > TABLE_SHARE::tdc.flushed and corresponding invariants be protected by > per-share TABLE_SHARE::tdc.LOCK_table_share instead of global LOCK_open. This looks pretty good to me! A couple of comments, see below. > === modified file 'sql/sql_plist.h' > --- a/sql/sql_plist.h 2013-11-20 11:05:39 +0000 > +++ b/sql/sql_plist.h 2014-03-15 18:53:01 +0000 > @@ -142,6 +142,14 @@ class I_P_List : public C, public I > > return result; > } > + inline T *back() > + { > + T *result= m_first; > + if (result) > + while (*B::next_ptr(result)) > + result= *B::next_ptr(result); > + return result; > + } I think this is wrong. The correct way would be to use I_P_List<> with the I_P_List_fast_push_back policy, then you could use have get_last() method to get the last element in the list. May be as inline T *back() { return *I::get_last(); } > void swap(I_P_List<T, B, C> &rhs) > { > swap_variables(T *, m_first, rhs.m_first); > > === modified file 'sql/table_cache.cc' > --- a/sql/table_cache.cc 2014-03-06 12:19:12 +0000 > +++ b/sql/table_cache.cc 2014-03-15 18:53:01 +0000 > @@ -70,13 +70,6 @@ static int32 tc_count; /**< Number of TA > > > /** > - Protects TABLE_SHARE::tdc.free_tables, TABLE_SHARE::tdc.all_tables. > -*/ > - > -mysql_mutex_t LOCK_open; So, you've now removed LOCK_open completely? Cool! > - > - > -/** > Protects unused shares list. > > TABLE_SHARE::tdc.prev > @@ -360,12 +378,15 @@ bool tc_release_table(TABLE *table) > table->in_use= 0; > /* Add table to the list of unused TABLE objects for this share. */ > table->s->tdc.free_tables.push_front(table); > - mysql_mutex_unlock(&LOCK_open); > + mysql_mutex_unlock(&table->s->tdc.LOCK_table_share); > return false; > > purge: > + /* Wait for MDL deadlock detector */ > + while (table->s->tdc.all_tables_refs) > + mysql_cond_wait(&table->s->tdc.COND_release, &table->s->tdc.LOCK_table_share); you're using it many times, I'd put it in a small static inline function, like static wait_for_mdl_deadlock_detector(TABLE *table) { mysql_mutex_assert_owner(&table->s->tdc.LOCK_table_share); while (table->s->tdc.all_tables_refs) mysql_cond_wait(&table->s->tdc.COND_release, &table->s->tdc.LOCK_table_share); } > tc_remove_table(table); > - mysql_mutex_unlock(&LOCK_open); > + mysql_mutex_unlock(&table->s->tdc.LOCK_table_share); > table->in_use= 0; > intern_close_table(table); > return true; Regards, Sergei [View Less]

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[Maria-developers] [GSOC 2014] GIS Enhancement
by bang honam 19 Mar '14

19 Mar '14

Hi everybody. I am Honam Bang, a researcher of Korean Institute of Science Technology and I will be a master student of UCSD, USA from this Sep. I have been working with GIS research for about one year. Therefore, I decided to work on the 'GIS Enhancement topic' because I have a lot of interest for dealing with geospatial data. My topic is 'implementing shp to sql command tool for MariaDB'. #MDEV-5813. Most shptosql tools are enable to convert 3D coordinates as I know. The shape file white … [View More]

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[Maria-developers] first results from replication benchmarks
by Axel Schwenke 18 Mar '14

18 Mar '14

Hi everybody, here are some first results from my benchmarks of replication / group commit performance. The benchmark is sysbench OLTP rw, data set fitting in memory. I tested a total of 27 configurations, 9 each for Maria-5.5.36, Maria-10.0.9 and MySQL-5.6.16. Variations were for binlog on/off, SBR vs. RBR and sync_binlog=0/1. For MariaDB I also tested XtraDB vs. InnoDB, for MySQL it was GTID on vs. GTID off. Not surprisingly turning on the binlog comes with a performance penalty. Also … [View More]

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[Maria-developers] Gsoc proposal submitted for user defined event
by Savita Agrawal 18 Mar '14

18 Mar '14

Hi, I have submitted my proposal for user defined event support project. I am still working on the proposal. Please give feedback. Regards, Savita

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[Maria-developers] Group commit id in mysqlbinlog output
by Kristian Nielsen 18 Mar '14

18 Mar '14

There was a question on the output of mysqlbinlog related to group commit. In 10.0, if two transactions group commit together on the master, their GTID event contains a "commit id" - a 64-bit number. This is used by parallel replication; if two transactions have the same commit id, they can be executed in parallel. In mysqlbinlog output, this looks like this: #140314 13:42:56 server id 1 end_log_pos 772 GTID 0-1-12 cid=180 ... #140314 13:42:56 server id 1 end_log_pos 1027 GTID 0-1-13 … [View More]

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Re: [Maria-developers] rbr triggers (all)
by Sergei Golubchik 18 Mar '14

18 Mar '14

Hi, Oleksandr! Ok to push. See a couple of comments below. On Mar 18, Oleksandr Byelkin wrote: > === added file 'mysql-test/suite/rpl/t/rpl_row_triggers.test' > --- mysql-test/suite/rpl/t/rpl_row_triggers.test 1970-01-01 00:00:00 +0000 > +++ mysql-test/suite/rpl/t/rpl_row_triggers.test 2014-03-11 08:49:31 +0000 > @@ -0,0 +1,280 @@ > +-- source include/have_binlog_format_row.inc > +-- source include/have_rbr_triggers.inc > +-- source include/master-slave.inc > +-- … [View More]

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Re: [Maria-developers] [Commits] Rev 3994: MDEV-5138 Numerous test failures in "mtr --ps --embedded"
by Sergei Golubchik 18 Mar '14

18 Mar '14

Hi, Holyfoot! On Dec 08, holyfoot(a)askmonty.org wrote: > ------------------------------------------------------------ > revno: 3994 > revision-id: holyfoot(a)askmonty.org-20131208143921-3veatgg9wngyzb47 > parent: holyfoot(a)askmonty.org-20131202104753-srqqm7hv1rtcurx4 > committer: Alexey Botchkov <holyfoot(a)askmonty.org> > branch nick: mdev-5138 > timestamp: Sun 2013-12-08 18:39:21 +0400 > message: > MDEV-5138 Numerous test failures in "mtr --ps --embedded".… [View More]

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Re: [Maria-developers] [Commits] Rev 3993: MDEV-5138 Numerous test failures in "mtr --ps --embedded"
by Sergei Golubchik 18 Mar '14

18 Mar '14

Hi, holyfoot! On Dec 02, holyfoot(a)askmonty.org wrote: > At file:///home/hf/wmar/mdev-5138/ > > ------------------------------------------------------------ > revno: 3993 > revision-id: holyfoot(a)askmonty.org-20131202104753-srqqm7hv1rtcurx4 > parent: holyfoot(a)askmonty.org-20131130142537-7j272euoaoy0svg1 > committer: Alexey Botchkov <holyfoot(a)askmonty.org> > branch nick: mdev-5138 > timestamp: Mon 2013-12-02 14:47:53 +0400 > message: > MDEV-5138 … [View More]

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Re: [Maria-developers] [Commits] Rev 3992: MDEV-5138 Numerous test failures in "mtr --ps --embedded". in file:///home/hf/wmar/mdev-5138/
by Sergei Golubchik 18 Mar '14

18 Mar '14

Hi, holyfoot! On Nov 30, holyfoot(a)askmonty.org wrote: > At file:///home/hf/wmar/mdev-5138/ > > ------------------------------------------------------------ > revno: 3992 > revision-id: holyfoot(a)askmonty.org-20131130142537-7j272euoaoy0svg1 > parent: holyfoot(a)askmonty.org-20131130132432-etlmes8qhhqhr1iu > committer: Alexey Botchkov <holyfoot(a)askmonty.org> > branch nick: mdev-5138 > timestamp: Sat 2013-11-30 18:25:37 +0400 > message: > MDEV-5138 … [View More]

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Re: [Maria-developers] MaxScale as a binlog server
by Kristian Nielsen 18 Mar '14

18 Mar '14

Mark Riddoch <mark.riddoch(a)skysql.com> writes: > we have been approached by a user with a suggestion for a project that we > might do with them. They have a replication environment with a large fan out > (100 slaves per master) and are looking at doing something to cut one the > load on the master. the thought they had was to use MaxScale to effectively > cache the bin log files, so MaxScale would act as a single Slave to the > Master and would itself have a number of … [View More]Slaves that read the bin log from > MaxScale. My initial response was why not just use an instance of MariaDB as > the intermediate node and connect slaves to one of those instances, in a > tree structure. They had a few reasons why they did not want to do this; > Looking in more detail I think it is feasible, we essentially write a router > module for MaxSale that acts as a slave, aching the bin log locally on the > MaxScale node. We then have another router, or maybe even the same one, that > relays that binlog to the real slaves. We are looking at doing something for > MariaDB 10, since we would want to utilise the GTID to get the best failover > semantics, I am assuming there must be some differences between the > replication stream that I can find documented for MySQL and what MariaDB 10 > does? Is this stuff anywhere on the Knowledge Base? I tried looking but Right, so I agree with what Serg said, that maybe going back to the original problem and seeing if there are better solutions possible would be better. However, I will try to answer the technical aspect here. I suppose caching and routing binlogs outside of the server should be possible, but it might be more complex than you would think at first. I am not aware of any comprehensive documentation for this. However, it should be relatively easy to see from the code. Basically, it is the function mysql_binlog_send() in sql/sql_repl.cc that handles sending binlog data to a slave. There are good comments in there describing many of the trickier points. You need to be aware that there is more logic in sending binlog data to a slave than just streaming raw binlog files. Maybe you can implement a subset and document any limitations. The old-style replication (not using GTID) is the simplest, but it still does a bit extra, like sending some extra events (FORMAT_DESCRIPTION_EVENT and fake ROTATE_EVENT). There is also the handling of old slaves. A slave sends a value in @mariadb_slave_capability, and the master will rewrite or remove any events that the slave does not understand, as appropriate. And there is the @@skip_replication flag; when the slave sets this, the master removes events that were logged with @@skip_replication set (to reduce bandwidth needs). The slave also does several SQL queries to obtain additional information. For example, the slave does a SELECT binlog_gtid_pos(file, offset) to obtain the GTID position associated with a given old-format replication position, so that it knows how to switch to GTID mode later. Maybe those queries could be handled by relaying them back to a real master server. The GTID mode is significantly more complex, due to a GTID position having multiple streams, one per replication domain. The slave sends @slave_connect_state, @slave_gtid_strict_mode, @slave_gtid_ignore_duplicates, and optionally @slave_until_gtid values. The router would need to parse these values and act accordingly. The binlog sender needs to keep track of each domain as the binlog files are scanned. Events in a domain must be skipped until the point specified in @slave_connect_state is reached. Then events are sent until the point in @slave_until_gtid is reached, at which point further events must again be skipped. The master also sends extra GTID_LIST events, which contain the state of the binlog at the point of the event, which is needed by the slave to correctly handle START SLAVE UNTIL master_gtid_pos=XXX and MASTER_GTID_WAIT(). A lot of effort was put into error handling, to support all reasonable, and even many unreasonable uses of replication, while still giving an error in cases where things are obviously wrong (to prevent silently doing the wrong thing or hanging). For example, if the slave tries to connect at a GTID that the master does not have, this is normally an error. This is important, because that GTID might be some transaction that was executed manually on the slave by mistake; if it only exists on the slave, then the master would endlessly skip events looking for the GTID that never shows up, and replication would silently hang. However, there are special cases where the slave _is_ allowed to connect at a GTID that does not exist on the master. For example, one might have a slave with --log-slave-updates=0. Then if this slave is promoted as a new master, the binlogs will not have the current position, but it is still allowed to connect to it at the point where it became the new master (but not to a point earlier than that). Another special case is if the requested GTID (but no GTIDs following that) was purged from the binary logs, as can easily happen if a replication domain is unused for long time. A _full_ implementation of a router for sending binlog to slaves would be some effort, but it might be reasonable to implement some subset. I suppose the first step would be for you to go through the code in mysql_binlog_send() and the functions it calls, and decide on which parts to implement. I will be happy to answer any questions that might pop up on the way, of course. > 2. They wanted to maintain the same group commit groups as the original > master, so as to benefit from the parallel replication. Note that this may no longer apply to MariaDB 10.0.9. The issue is that an intermediate slave that is itself a master may have less group commit than the original master, which reduces the possibility for a third-level slave to efficiently do parallel replication. But in 10.0.9, it should be possible to configure the intermediate slave with --binlog-commit-wait-* to get better group commit. > 3. They think that can get better failover semantics because they will have > n (maybe 5 or 10) MaxScales and they will all have the same bin log, so > failover between them will be easier. I am curious how it will be assured that they all have the same binlog in case of crash? But maybe you just mean that all will be a subset of the largest one. Hope this helps, - Kristian. [View Less]

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[Maria-developers] Java Connector Discussion
by Puneet Dewan 18 Mar '14

18 Mar '14

Hi Georg, As we missed our scheduled meeting yesterday, can you suggest a suitable time to discuss? Regards Puneet.

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Re: [Maria-developers] [Maria-discuss] MariaDB vs. MySQL error codes (1900+)
by Kristian Nielsen 17 Mar '14

17 Mar '14

Felipe Gasper <felipe(a)felipegasper.com> writes: > Hi everyone, > > I notice that MariaDB is using the 1900+ range for its own > error codes; however, MySQL 5.7, at least, has a few errors in that > range as well. > > Are error codes just going to be an area of increasing > conflict between the two, or is there a plan to migrate MariaDB codes > to a different numbering scheme? Thanks for bringing this to attention. This is a pretty serious issue, and I've … [View More]

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[Maria-developers] redundant compilation of targets in mariadb 10.0
by Rohit Kalhans 17 Mar '14

17 Mar '14

hello all, I am trying to fix a few bugs but ever after small modifications in specific files, make command build all targets irrespective of whether or not they are dependent on the modified source. I am no expert in build commands but this seem off since it keeps taking exceptionally long time to build. Is there a trick/workaround that can prevent all targets from being built. Or am I missing something. -- Cheerio! *Rohit* *http://rohitkalhans.com <http://rohitkalhans.com>*

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[Maria-developers] For Google Summer of Code 2014, Interested in the task of "statistically optimize mysql-test runs by running less tests"
by 胡仲义 17 Mar '14

17 Mar '14

Dear Sergei Golubchik, I am a post graduate student of Institute of Software, Chinese Academy of Sciences and my name is Zhongyi Hu. I major in computer science and my research field is data stream mining. Because I have got enough papers and works for graduation, I want to do something interesting, meaningful and valuable in the rest time as student. I have participated in two projects about database, one is main memory database and the other is database cluster. I got some experience of … [View More]

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[Maria-developers] [GSOC 2014] "CREATE OR REPLACE, CREATE IF NOT EXISTS, and DROP IF EXISTS" Project
by sriram patil 16 Mar '14

16 Mar '14

Hi Sergei, I am Sriram Patil. I am a Masters' student at International Institute of Information Technology, Hyderabad, India. I have been working on a small DB Engine as part of my course work in C++. I have also worked on a SQLite DB abstraction library FMDB in Objective-C. Also, I am currently working on lock-free concurrent B-trees (Java), and going to evaluate it with an in-memory database to check the performance. I have also worked on libdaap and Rhythembox source code during my … [View More]

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[Maria-developers] MDEV-5681- audit log not rotating
by Tan Tran 14 Mar '14

14 Mar '14

Hi maria-developers, This is my patch for MDEV-5681: " audit log will not rotate when the file size exceeds global variable setting": http://bazaar.launchpad.net/~tktran/maria/maria-fix-bug5681/revision/4102 To test, 1. set server_audit_events = 'connect' and keep default rotate size of 1000000. 2. connect with a bad password about 20 times: for i in {1..20}; do mysql -ufail -pfail; done 3. see that server_audit.log is X bytes 4. set server_audit_rotate_size = 1000 5. connect with bad … [View More]

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Re: [Maria-developers] [Commits] Rev 4066: MDEV-5089 - possible deadlocks between rwlocks and mutexes
by Sergei Golubchik 13 Mar '14

13 Mar '14

Hi, Sergey! On Feb 13, Sergey Vojtovich wrote: > revno: 4066 > revision-id: svoj(a)mariadb.org-20140213074049-70zbqa98y95sfpox > parent: sanja(a)askmonty.org-20140212150705-e1tfabmhjggqws7q > committer: Sergey Vojtovich <svoj(a)mariadb.org> > branch nick: 5.5 > timestamp: Thu 2014-02-13 11:40:49 +0400 > message: > MDEV-5089 - possible deadlocks between rwlocks and mutexes > > Pre-MDL versions had direct relationship between LOCK_open and > … [View More]

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[Maria-developers] TokuDB Performance Regression (MDEV-5777)
by Tim Callaghan 13 Mar '14

13 Mar '14

I'm very concerned about the regression I reported in https://mariadb.atlassian.net/browse/MDEV-5777, as users of the MariaDB.org supplied builds of both 5.5 and 10.0 are getting substantially less throughput than the MariaDB 5.5 build supplied by us at tokutek.com. I see that the fix version is now 5.5.37 and 10.0.10, is there a plan for how that will get done? I'll assist if possible, I just don't know how I can. -Tim Callaghan (Tokutek)

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