Uploaded image for project: 'MariaDB Server'
  1. MariaDB Server
  2. MDEV-19212

4GB Limit on large_pages (innodb_buffer_pool_chunk_size) - integer overflow

    Details

      Description

      From upstream bug, https://bugs.mysql.com/bug.php?id=94747, publicity thanks to Valerii

      Allocations of 4G+ innodb_buffer_pool_chunk_size results in int overflow:

      10.4.4

      sql/mysqld --no-defaults --skip-networking --datadir=/tmp/datadir --log-bin=/tmp/datadir/mysqlbin --socket /tmp/s.sock --lc-messages-dir=/home/dan/repos/build-mariadb-server-10.4-upstream/sql/share --innodb_buffer_pool_instances=1 --large-pages --innodb_buffer_pool_chunk_size=4G --innodb_buffer_pool_size=8G --verbose
       
      2019-04-08 10:20:50 0 [Note] /home/dan/repos/build-mariadb-server-10.4-upstream/sql/mysqld (mysqld 10.4.4-MariaDB-log) starting as process 32260 ...
       
      Thread 1 "mysqld" hit Breakpoint 1, os_mem_alloc_large (n=n@entry=0x7fffffff59b0) at /home/dan/repos/mariadb-server/storage/innobase/os/os0proc.cc:66
      66	{
      (gdb) p *n
      $1 = 4391436288
      (gdb) n
      73		if (!os_use_large_pages || !os_large_page_size) {
      (gdb) p os_large_page_size 
      $2 = 2097152
      (gdb) n
      79		size = ut_2pow_round(*n + (os_large_page_size - 1),
      (gdb) n
      82		shmid = shmget(IPC_PRIVATE, (size_t) size, SHM_HUGETLB | SHM_R | SHM_W);
      (gdb) p size
      $3 = 96468992
      (gdb) n
      83		if (shmid < 0) {
      (gdb) 
      84			ib::warn() << "Failed to allocate " << size
      (gdb) 
      85				<< " bytes. errno " << errno;
      (gdb) 
      2019-04-08 10:25:48 0 [Warning] InnoDB: Failed to allocate 96468992 bytes. errno 22
      108		ib::warn() << "Using conventional memory pool";
      

      5.5 instance doesn't support chunk size - but seemed unaffected

      190408 10:29:29 [Note] /home/dan/repos/build-mariadb-5.5/sql/mysqld (mysqld 5.5.64-MariaDB) starting as process 26248 ...
      Warning: Failed to allocate 130023424 bytes from HugeTLB memory. errno 22
      Warning: Using conventional memory pool
      [New Thread 0x7ffff6dff700 (LWP 26255)]
      190408 10:29:29 InnoDB: The InnoDB memory heap is disabled
      190408 10:29:29 InnoDB: Mutexes and rw_locks use GCC atomic builtins
      190408 10:29:29 InnoDB: Compressed tables use zlib 1.2.11
      190408 10:29:29 InnoDB: Using Linux native AIO
      190408 10:29:29 InnoDB: Initializing buffer pool, size = 8.0G
       
      Thread 1 "mysqld" hit Breakpoint 1, os_mem_alloc_large (n=n@entry=0x7ffff72eb258, populate=populate@entry=0)
          at /home/dan/repos/mariadb-server-5.5/storage/xtradb/os/os0proc.c:112
      112		if (!os_use_large_pages || !os_large_page_size) {
      Missing separate debuginfos, use: dnf debuginfo-install jemalloc-5.1.0-2.fc29.x86_64 libxcrypt-4.4.4-2.fc29.x86_64
      (gdb) p os_large_page_size 
      $1 = 2097152
      (gdb) p *n
      $2 = 8816427008
      (gdb) n
      118		size = ut_2pow_round(*n + (os_large_page_size - 1),
      (gdb) n
      121		shmid = shmget(IPC_PRIVATE, (size_t)size, SHM_HUGETLB | SHM_R | SHM_W);
      (gdb) p size
      $3 = 8816427008
      (gdb) n
      122		if (shmid < 0) {
      (gdb) 
      123			fprintf(stderr, "InnoDB: HugeTLB: Warning: Failed to allocate"
      (gdb) 
      InnoDB: HugeTLB: Warning: Failed to allocate 8816427008 bytes. errno 22
      141		if (ptr) {
      (gdb) quit
      

      After changing os_large_page_size back to ulint (from uint where it was changed in 2e814d4702d71a04388386a9f591d14a35980bfe Merge InnoDB 5.7 from mysql-5.7.9) this is corrected:

      2019-04-08 10:57:07 0 [Note] /home/dan/repos/build-mariadb-server-10.4/sql/mysqld (mysqld 10.4.5-MariaDB-debug-log) starting as process 21743 ...
      2019-04-08 10:57:07 0 [Warning] Could not increase number of max_open_files to more than 4096 (request: 4190)
      2019-04-08 10:57:07 0 [Warning] Changed limits: max_open_files: 4096  max_connections: 151 (was 151)  table_cache: 1957 (was 2000)
      [New Thread 0x7ffff70e3700 (LWP 21772)]
      Warning: Failed to allocate 130023424 bytes from HugeTLB memory. errno 22
      Warning: Using conventional memory pool
      [New Thread 0x7fffe25ff700 (LWP 21782)]
      2019-04-08 10:57:07 0 [Note] InnoDB: Using Linux native AIO
      2019-04-08 10:57:07 0 [Note] InnoDB: !!!!!!!! UNIV_DEBUG switched on !!!!!!!!!
      2019-04-08 10:57:07 0 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
      2019-04-08 10:57:07 0 [Note] InnoDB: Uses event mutexes
      2019-04-08 10:57:07 0 [Note] InnoDB: Compressed tables use zlib 1.2.11
      2019-04-08 10:57:07 0 [Note] InnoDB: Number of pools: 1
      2019-04-08 10:57:07 0 [Note] InnoDB: Using SSE2 crc32 instructions
      2019-04-08 10:57:07 0 [Note] mysqld: O_TMPFILE is not supported on /tmp (disabling future attempts)
      2019-04-08 10:57:07 0 [Note] InnoDB: Initializing buffer pool, total size = 8G, instances = 1, chunk size = 4G
       
      Thread 1 "mysqld" hit Breakpoint 1, os_mem_alloc_large (n=0x7fffffff8ba0) at /home/dan/repos/mariadb-server-10.4/storage/innobase/os/os0proc.cc:66
      66	{
      Missing separate debuginfos, use: dnf debuginfo-install libxcrypt-4.4.4-2.fc29.x86_64 openssl-libs-1.1.1b-3.fc29.x86_64
      (gdb) p *n
      $1 = 4294967296
      (gdb) n
      73		if (!os_use_large_pages || !os_large_page_size) {
      (gdb) p os_large_page_size 
      $2 = 2097152
      (gdb) n
      78		ut_ad(ut_is_2pow(os_large_page_size));
      (gdb) 
      79		size = ut_2pow_round(*n + (os_large_page_size - 1),
      (gdb) 
      82		shmid = shmget(IPC_PRIVATE, (size_t) size, SHM_HUGETLB | SHM_R | SHM_W);
      (gdb) p size
      $3 = 4294967296
      (gdb) n
      

      tested in 10.3 and also corrected.

      Note MDEV-18851 will correct the 10.4 version by removing os_large_page_size

        Attachments

          Activity

            People

            • Assignee:
              marko Marko Mäkelä
              Reporter:
              danblack Daniel Black
            • Votes:
              0 Vote for this issue
              Watchers:
              3 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved: