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  • <div><p>该提问来源于开源项目:apache/accumulo</p></div>
  • <p>On saving some heavy pages the following error occurs: <pre><code> Wikimedia\Rdbms\DBQueryError from line 1603 of /var/...
  • The inserts on truncated table are anyway blocked because of MDL. <p>Block of unrelated inserts on different tables is the core problem here. TRUNCATE TABLE t1 can cause INSERT INTO t2 ..() or SELECT...
  • UPDATE statement on table 'data_table' expected to update 33 row(s); 32 were matched.: StaleDataError Traceback (most recent call last): File "/var/task/saving/rds/serverless.py", line...
  • <p><strong>Use case</strong>: Have a new timeout setting for table option write.wait_for_active_shards. Currently it is default to 30 seconds, and don't think it is configurable. <p><strong>...
  • 模拟cursor pin S wait on X

    2014-07-06 13:58:55
    模拟cursor pin S wait on X create table test tablespace users as select *from dba_objects; BEGIN DBMS_STATS.GATHER_TABLE_STATS(ownname => 'TEST', tabname
    <pre name="code" class="sql">模拟cursor pin S wait on X
    
    create table test tablespace users as select *from dba_objects;  
    
    BEGIN
      DBMS_STATS.GATHER_TABLE_STATS(ownname          => 'TEST',
                                    tabname          => 'TEST',
                                    estimate_percent => 30,
                                    method_opt       => 'for all columns size repeat',
                                    no_invalidate    => FALSE,
                                    degree           => 8,
                                    cascade          => TRUE);
    END;
    /
    
    
    测试开始:
    这是10.2版本提出的mutex(互斥)机制用来解决library cache bin latch争夺问题引入的新事件,是否使用这种机制受到隐含参数_kks_use_mutex_pin的限制,从10.2.0.2开始该参数default为true,使用
    
    这种机制oracle是为了解决library cache bin latch的串行使用问题,但是mutex貌似还不是很稳定,在很多系统中会出现cursor: pin S wait on X等待事件,这个事件和mutex的使用有关:
    SQL> SELECT nam.ksppinm NAME, val.ksppstvl VALUE
      2  FROM x$ksppi nam, x$ksppsv val
      3  WHERE nam.indx = val.indx AND nam.ksppinm LIKE '%mutex%'
      4  ORDER BY 1;
    NAME                                               VALUE
    -------------------------------------------------- ----------------------------------------
    _kks_use_mutex_pin                                 TRUE
    
    SQL> select * from v$version;
    
    BANNER
    ----------------------------------------------------------------
    Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - Prod
    PL/SQL Release 10.2.0.4.0 - Production
    CORE	10.2.0.4.0	Production
    TNS for Linux: Version 10.2.0.4.0 - Production
    NLSRTL Version 10.2.0.4.0 - Production
    
    测试数据库版本:
    SQL> SELECT nam.ksppinm NAME, val.ksppstvl VALUE
      FROM x$ksppi nam, x$ksppsv val
     WHERE nam.indx = val.indx
       AND nam.ksppinm LIKE '%mutex%'
     ORDER BY 1;  2    3    4    5  
    
    NAME							     VALUE
    ------------------------------------------------------------ ----------
    _kks_use_mutex_pin					     TRUE
    
    
    
    
    select SESSION_ID,
    ash.sample_time,
           NAME,
           P1,
           P2,
           P3,
           WAIT_TIME,
           CURRENT_OBJ#,
           CURRENT_FILE#,
           CURRENT_BLOCK#
      from v$active_session_history ash, v$event_name enm
     where ash.event# = enm.event#
    
            SESSION_ID   SANMPLE_TIME                 NAME                    P1            P2
    1	1629	08-7月 -14 01.24.43.480 上午	cursor: pin S	          870994415	1	327689	0	-1	0	0
    2	1629	08-7月 -14 01.24.42.480 上午	cursor: pin S	          870994415	1	327689	0	-1	0	0
    3	1626	08-7月 -14 01.24.41.480 上午	cursor: pin S wait on X	  914340628	106758144	327686	0	-1	0	0
    4	1627	08-7月 -14 01.24.40.480 上午	cursor: pin S	          1774050780	1	589825	0	-1	0	0
    5	1626	08-7月 -14 01.24.39.470 上午	cursor: pin S wait on X	  202989082	106758144	327687	0	-1	0	0
    6	1624	08-7月 -14 01.24.38.470 上午	cursor: pin S wait on X	  172408315	106758144	327685	0	-1	0	0
    7	1624	08-7月 -14 01.24.37.470 上午	cursor: pin S	          4107572888	106627073	327687	0	-1	0	0
    8	1634	08-7月 -14 01.24.37.470 上午	latch: library cache	  589581072	215	0	0	-1	0	0
    9	1624	08-7月 -14 01.24.36.470 上午	cursor: pin S	          4107572888	106627073	327687	0	-1	0	0
    10	1627	08-7月 -14 01.24.35.470 上午	latch: library cache	  589581072	215	0	0	-1	0	0
    11	1634	08-7月 -14 01.24.35.470 上午	cursor: pin S wait on X	  4718305	106627072	327688	0	-1	0	0
    
    
    select SESSION_ID,
    ash.sample_time,
           NAME,
           P1,
           P2,
           P3,
           WAIT_TIME,
           CURRENT_OBJ#,
           CURRENT_FILE#,
           CURRENT_BLOCK#
      from v$active_session_history ash, v$event_name enm
     where ash.event# = enm.event#
    1	1631	08-7月 -14 01.14.57.196 上午	cursor: pin S wait on X	3719301976	0	327681	0	-1	0	0
    
    
    select b.*, sq.sql_text
      from v$session se,
           v$sql sq,
           (select a.*, s.sql_text
              from v$sql s,
                   (select sid,
                           event,
                           wait_class,
                           p1,
                           p2raw,
                           to_number(substr(p2raw, 1, 4), 'xxxx') sid_hold_mutex_x
                      from v$session_wait
                     where event like 'cursor%') a
             where s.HASH_VALUE = a.p1) b
     where se.sid = b.sid
       and se.sql_hash_value = sq.hash_value;
    
            SID      EVENT                                                                 sid_hold_mutex_x
    1	1637	cursor: pin S wait on X	Concurrency	4286791313	065F0000	1631	select object_id from test t where object_id=89	declare   v_string varchar2(100) 
    
    := 'alter system flush shared_pool';   msql     varchar2(200); begin   loop     for i in 1 .. 100 loop       msql := 'select object_id from test t where object_id=' || i;       
    
    execute immediate msql;     end loop;   end loop; end;
    
                                                                        sid_hold_mutex_x 
    1	1627	cursor: pin S	Other	868910173	065D0001	1629	select object_id from test t where object_id=3	select object_id from test t where object_id=3
    
    
                                                                                        sid_hold_mutex_x
    2	1631	cursor: pin S wait on X	Concurrency	4107572888	065B0000	1627	select object_id from test t where object_id=100	select object_id from 
    
    test t where object_id=60


    
    
    展开全文
  • Replacing old systems table with new systems table and re-indexing - please wait" for the last 8 hours and it has made no progress and the entire program is locked down and not responding to any ...
  • <div><p>Open a XLSX file with a long Pivot table in OO 6.0 ...I think the cursor moves on Pivot table but it doesn't show to user</p><p>该提问来源于开源项目:ONLYOFFICE/DocumentServer</p></div>
  • <p>One workaround is to commit enough models early enough that no model needs to wait on more than one other model. This workaround is hard to use, however. If we need to create a large network of ...
  • I am trying to bind a list to an odata v4 table with a composite key. The key consists of three attributes fkProfile, Weekday and MealNumber. <p><img width="724" alt="bildschirmfoto 2019-02-05 um 00 ...
  • RESTORE SNAPSHOT snapshots.snapshot_prod_2016_03_01 TABLE events_2015_10 WITH (wait_for_completion=true); </code></pre> <p>I get: <pre><code> SQLActionException[[snapshots:snapshot_prod_2016_03_...
  • System.Threading.SynchronizationLockException: Cannot wait on monitors on this runtime. </code></pre> <p>See details below. <h2>Steps to Reproduce (for bugs) <p>Create a test DynamoDB table called ...
  • <div><p>Instead of computing the columns and their widths based only on the first point that arrives, delay for a configurable amount for more points to arrive. <p>As part of this change, remove the ...
  • 今天在查HBASE表时,一批次大概千万条数据, 表结构 rowkey是三个关键信息拼接的,A,B,C A 和 C 是多对多的关系, ...org.apache.hadoop.hbase.ipc.CallTimeoutException: Call id=6, waitTime=60030, rpcTimeout=

    今天在查HBASE表时,一批次大概千万条数据,
    表结构 rowkey是三个关键信息拼接的,A,B,C A 和 C 是多对多的关系,
    在只有第一信息的情况下使用HBASE的范围查询+模糊查询,setStartRow(A) ,setStopRow(A),RowFilter(RegexStringComparator©)

    查询时报错:
    org.apache.hadoop.hbase.ipc.CallTimeoutException: Call id=6, waitTime=60030, rpcTimeout=60000 rpcTimeout=60000
    row ‘12F3X’ on table ‘HBASETABLE’ at region=XXXX., hostname=XXX, seqNum=XX

    只看报错中 12F3X,不是HBASETABLE的完整Rowkey,而是设置的setStartRow(A),并且通过HBASE shell可以拿到12F3X对应的数据,那会是神马原因呢

    网上给出许多建议

    1.1 HBase有很多超时机制,本次报错应当是RPC超时引起的,可根据实际情况适当调整如下参数解决:
    Set mapreduce.task.timeout= 1200000
    set hbase.client.scanner.timeout.period=600000
    set hbase.rpc.timeout=600000
    其中, hbase.client.scanner.timeout.period和hbase.rpc.timeout最好配置一样大

    1.2 超时时长解决方法:
       (1)-增加超时时长;
       (2)-减少缓存条数;setCaching(100),但问题不再此处,因为取的每条数据很小,总的两千条也不会暂用很多的内存;
       (3)-过滤器原因:因为过滤查询和前缀查询的速度比较慢。所以在扫描的块中分布的合格的条数比例很小时,会很难再短时间内读取2000条数据 或者在当前的region中找不到数据时会与其他region做比对,确认数据是否真的不存在,解决方法,用范围查询代替前缀查询或模糊查询的动作。
       (4)-创建索引表: HBase 中的二级索引是通过建表的方式实现的,将能拿到A的表按照 C,A,B的格式作为rowkey新建一张索引表,拿到 A B C 后,再通过get的方式获取数据

    这样看来最可能是RowFIlter使用的原因了
    使用(4),最后问题解决!

    疑问:
    过滤器效率很慢,那其存在的意义???

    附上 过滤器 使用的example
    https://blog.csdn.net/zhangketuan/article/details/50528767

    展开全文
  • <div><p>On a table with <code>WINDOW</code> and <code>RETENTION</code> settings, windows are kept long after expiration (possibly never deleted) <p><strong>To Reproduce 1. ksqlDB 0.9.0 2. Create a ...
  • : \n \n SQLSTATE[42S01]: Base table or view already exists: 1050 Table 'storage_loc \n ation' already exists \n \n\nIn Exception....
  • So, I think it is a bug related to AO table, I have a glance on the source, found that in function DefineIndex() defined in file src/backend/commands/indexcmds.c, the lock aquired by AO table is ...
  • <div><p>I wrote a simple stress test to see if the new InterprocessCondVar would let us use wait_for_change() on Apple platforms. Unfortunately, it consistently either deadlocks (possibly due to bugs ...
  • I adapted raydium-rm68200 to innolux, p101dbz, change match table, reset timing, init sequences but without changing filename. I traced into source code and I found that IRQ(vc4_dsi_irq_defer_to_...
  • m trying to convert my backend scraper to an on-device scraper using your library, but I'm finding it hard to understand the documentation without examples, how would one use WKZombie to login and...
  • HINT: Process 17284 will wait for gp_debug_linger=120 seconds before termination. Note that its locks and other resources will not be released until then. server closed the connection unexpectedly...
  • // 7 threads wait here for the "mutex" held by 8th thread <p>Here's the problem, all 8 threads have same input parameters (shown below) to the function <strong>dbuf_find</strong> - 0...
  • /* if already waiting on list, if no new ah just ret */ if (pt->ah_count_in_use == context->max_http_header_pool) { lwsl_err("ah wl denied\n"); goto bail; } /* new ah.... ...
  • 1. How can I retrieve the text (from PDF table) in correct format ? 2 Or, how can I execute command from other OCR library such as tesseract? <p>Please advice. <p>Thanks! Regards, Mandar.</p><p>该提问...
  • Database error: Error: Error: near line 1: no such table: albums /home/arnaud/htdocs/node_modules/mediacenterjs/apps/music/music-functions.js:118 if (typeof rows !== 'undefined' &...
  • constraint WH_ProductLog_wH_Tyre_fkey on table \\\\\\\"WH_ProductLog\\\\\\\" depends on table \\\\\\\"WH_Tyre\\\\\\\"\\\"), hint: Some(\\\"Use DROP ... CASCADE to drop the ...
  • <p>data.table is listed on my DESCRIPTION file under <strong>Imports</strong> part. </li><li> <p>my travis build config file <strong>.travis.yml.</strong> : </li></ol> <p>language: R r: bioc-release ...
  • <div><p>When I have nodes that leave the network (actively powered off), they still seem to linger on in the network, and no matter how long I wait, the mesh doesn't seem to look for stale entries...
  • Warning: WARNING: the kernel failed to re-read the partition table on /dev/sdb (Device or resource busy). As a result, it may not reflect all of your changes until after reboot. </code></pre> <p>...
  • LOCK WAIT 6 lock struct(s), heap size 1184, 3 row lock(s), undo log entries 1 MySQL thread id 7004, OS thread handle 0x7f387011e700, query id 4512165 10.0.0.6 pimcoreuser update INSERT INTO `...

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