Uploaded image for project: 'MariaDB Server'
  1. MariaDB Server
  2. MDEV-27326

Mariabackup being overwhelmed during the prepare phase while using 32GB of memory

    XMLWordPrintable

    Details

    • Type: Bug
    • Status: Closed (View Workflow)
    • Priority: Critical
    • Resolution: Fixed
    • Affects Version/s: 10.2.27
    • Fix Version/s: N/A
    • Component/s: Backup, Documentation
    • Labels:
      None
    • Environment:
      RHEL

      Description

      During the restore step the customer was getting "Restore failed on 10.2.27 with signal 6 and 11"

      Oct 9 08:19:43 db166020 kernel: [5710622.181729] mariabackup[143845]: segfault at 0 ip 0000561e04a2dc88 sp 00007f2b853d97f0 error 6 in mariabackup[561e041da000+913000]

      Below is the stack trace from the mariabackup output:

      2021-10-09  8:19:42 139824895743744 [ERROR] [FATAL] InnoDB: is_short 0, info_and_status_bits 0, offset 10140, o_offset 9, mismatch index 18446744073709551594, end_seg_len 31 pars
      ed len 3
      211009  8:19:42 [ERROR] mysqld got signal 6 ;
      This could be because you hit a bug. It is also possible that this binary
      or one of the libraries it was linked against is corrupt, improperly built,
      or misconfigured. This error can also be caused by malfunctioning hardware.
       
      To report this bug, see https://mariadb.com/kb/en/reporting-bugs
       
      We will try our best to scrape up some info that will hopefully help
      diagnose the problem, but since we have already crashed,
      something is definitely wrong and this may fail.
       
      Server version: 10.2.27-MariaDB
      key_buffer_size=0
      read_buffer_size=131072
      max_used_connections=0
      max_threads=1
      thread_count=0
      It is possible that mysqld could use up to
      key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 5419 K  bytes of memory
      Hope that's ok; if not, decrease some variables in the equation.
       
      Thread pointer: 0x0
      Attempting backtrace. You can use the following information to find out
      where mysqld died. If you see no messages after this, something went
      terribly wrong...
      stack_bottom = 0x0 thread_stack 0x49000
      /glide/mariadb/10.2.27snc2/bin/mariabackup(my_print_stacktrace+0x2e)[0x561e04a30c7e]
      mysys/stacktrace.c:268(my_print_stacktrace)[0x561e044d554d]
      sigaction.c:0(__restore_rt)[0x7f3412b5e630]
      :0(__GI_raise)[0x7f3411968387]
      :0(__GI_abort)[0x7f3411969a78]
      ut/ut0ut.cc:645(ib::fatal::~fatal())[0x561e0482e823]
      page/page0cur.cc:1200(page_cur_parse_insert_rec(unsigned long, unsigned char const*, unsigned char const*, buf_block_t*, dict_index_t*, mtr_t*))[0x561e0474df9b]
      log/log0recv.cc:1655(recv_parse_or_apply_log_rec_body(mlog_id_t, unsigned char*, unsigned char*, unsigned long, unsigned long, bool, buf_block_t*, mtr_t*))[0x561e0472c1d1]
      log/log0recv.cc:2162(recv_recover_page(buf_block_t*, mtr_t&, recv_addr_t*, unsigned long))[0x561e0472ce19]
      log/log0recv.cc:2272(recv_recover_page(buf_page_t*))[0x561e041eb78d]
      buf/buf0buf.cc:6164(buf_page_io_complete(buf_page_t*, bool, bool))[0x561e0461eb9c]
      fil/fil0fil.cc:5169(fil_aio_wait(unsigned long))[0x561e0466c461]
      srv/srv0start.cc:331(io_handler_thread)[0x561e047e0da8]
      pthread_create.c:0(start_thread)[0x7f3412b56ea5]
      /lib64/libc.so.6(clone+0x6d)[0x7f3411a309fd]
      The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
      information that should help you find out what is causing the crash.
      Writing a core file...
      Working directory at /glide/mysqld/customecert_3400_peta/temp/restore_2021-10-08_1820332/customer_3400_db170011_s_2021-10-08_0612271
      Resource Limits:
      Fatal signal 11 while backtracing
      

      The customer managed to capture thread dumps and the mariabakcup log, which I have attached to this ticket.

      Unfortunately, there was no cored dump capture during said event.

      Furthermore, the customer was able to avoid the mariabackup crash during the restore by increasing the previously sizeable "--use-memory" of 32GB to 256GB. However they did not see the following log:

      [Warning] InnoDB: Difficult to find free blocks in the buffer pool (21 search iterations)! 21 failed attempts to flush a page! Consider increasing innodb_buffer_pool_size. Pending flushes (fsync) log: 0; buffer pool: 0. 5129 OS file reads, 0 OS file writes, 0 OS fsyncs. 
      

      Therefore, it does not seem related to https://jira.mariadb.org/browse/MDEV-20679 as I had initially hoped.

      If you require any other information, please let us know.

        Attachments

          Issue Links

            Activity

              People

              Assignee:
              GeoffMontee Geoff Montee
              Reporter:
              scottsommerville Scott Sommerville
              Votes:
              1 Vote for this issue
              Watchers:
              9 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved:

                  Git Integration

                  Error rendering 'com.xiplink.jira.git.jira_git_plugin:git-issue-webpanel'. Please contact your Jira administrators.