rocksdb/env/io_posix.cc:449: rocksdb::PosixMmapReadableFile::PosixMmapReadableFile(int, const string&, void*, size_t, const rocksdb::EnvOptions&): Assertion `!options.use_direct_reads' failed.

[george-lorch]

I believe this is similar but different from #778

I reproduced this on facebook-mysql-5.6.35 at commit 414870a

Start mysqld with "--rocksdb-use-direct-io-for-flush-and-compaction=1 --rocksdb-block-cache-size=10000000 --rocksdb-allow-mmap-reads=1" on tmpfs and get the following callstack:

mysqld: /home/glorch/dev/ps/facebook-mysql/rocksdb/env/io_posix.cc:449: rocksdb::PosixMmapReadableFile::PosixMmapReadableFile(int, const string&, void*, size_t, const rocksdb::EnvOptions&): Assertion `!options.use_direct_reads' failed.

Thread 1 "mysqld" received signal SIGABRT, Aborted.
__GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
51 ../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
#1 0x00007ffff5915801 in __GI_abort () at abort.c:79
#2 0x00007ffff590539a in __assert_fail_base (fmt=0x7ffff5a8c7d8 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x555557478f4f "!options.use_direct_reads",
file=file@entry=0x555557478c98 "/home/glorch/dev/ps/facebook-mysql/rocksdb/env/io_posix.cc", line=line@entry=449,
function=function@entry=0x55555747af60 <rocksdb::PosixMmapReadableFile::PosixMmapReadableFile(int, std::__cxx11::basic_string<char, std::char_traits, std::allocator > const&, void*, unsigned long, rocksdb::EnvOptions const&)::PRETTY_FUNCTION> "rocksdb::PosixMmapReadableFile::PosixMmapReadableFile(int, const string&, void*, size_t, const rocksdb::EnvOptions&)") at assert.c:92
#3 0x00007ffff5905412 in __GI___assert_fail (assertion=0x555557478f4f "!options.use_direct_reads", file=0x555557478c98 "/home/glorch/dev/ps/facebook-mysql/rocksdb/env/io_posix.cc", line=449,
function=0x55555747af60 <rocksdb::PosixMmapReadableFile::PosixMmapReadableFile(int, std::__cxx11::basic_string<char, std::char_traits, std::allocator > const&, void*, unsigned long, rocksdb::EnvOptions const&)::PRETTY_FUNCTION> "rocksdb::PosixMmapReadableFile::PosixMmapReadableFile(int, const string&, void*, size_t, const rocksdb::EnvOptions&)") at assert.c:101
#4 0x0000555556e6ea75 in rocksdb::PosixMmapReadableFile::PosixMmapReadableFile (this=0x5555583452d0, fd=6, fname="./.rocksdb/IDENTITY", base=0x7ffff7ff4000, length=37, options=...) at /home/glorch/dev/ps/facebook-mysql/rocksdb/env/io_posix.cc:449
#5 0x0000555556e61309 in rocksdb::(anonymous namespace)::PosixEnv::NewRandomAccessFile (this=0x555557f5ff20 rocksdb::Env::Default()::default_env, fname="./.rocksdb/IDENTITY", result=0x7fffffffbd50, options=...)
at /home/glorch/dev/ps/facebook-mysql/rocksdb/env/env_posix.cc:231
#6 0x0000555556d378e0 in rocksdb::DBImpl::Recover (this=0x555558346af0, column_families=std::vector of length 2, capacity 2 = {...}, read_only=false, error_if_log_file_exist=false, error_if_data_exists_in_logs=false)
at /home/glorch/dev/ps/facebook-mysql/rocksdb/db/db_impl_open.cc:368
#7 0x0000555556d3c060 in rocksdb::DBImpl::Open (db_options=..., dbname="./.rocksdb", column_families=std::vector of length 2, capacity 2 = {...}, handles=0x7fffffffc800, dbptr=0x7fffffffc3c8, seq_per_batch=false, batch_per_txn=true)
at /home/glorch/dev/ps/facebook-mysql/rocksdb/db/db_impl_open.cc:1127
#8 0x00005555570168d5 in rocksdb::TransactionDB::Open (db_options=..., txn_db_options=..., dbname="./.rocksdb", column_families=std::vector of length 2, capacity 2 = {...}, handles=0x7fffffffc800, dbptr=0x555557f3ea80 myrocks::rdb)
at /home/glorch/dev/ps/facebook-mysql/rocksdb/utilities/transactions/pessimistic_transaction_db.cc:236
#9 0x0000555556bc29bf in myrocks::rocksdb_init_func (p=0x5555583358a0) at /home/glorch/dev/ps/facebook-mysql/storage/rocksdb/ha_rocksdb.cc:4859
#10 0x000055555626dc6b in ha_initialize_handlerton (plugin=0x555558329200) at /home/glorch/dev/ps/facebook-mysql/sql/handler.cc:655
#11 0x00005555564ad227 in plugin_initialize (plugin=0x555558329200) at /home/glorch/dev/ps/facebook-mysql/sql/sql_plugin.cc:1163
#12 0x00005555564add2d in plugin_init (argc=0x555557ed1410 <remaining_argc>, argv=0x5555581d94f0, flags=0) at /home/glorch/dev/ps/facebook-mysql/sql/sql_plugin.cc:1465
#13 0x000055555623cc27 in init_server_components () at /home/glorch/dev/ps/facebook-mysql/sql/mysqld.cc:6010
#14 0x00005555562401f3 in mysqld_main (argc=18, argv=0x5555581d94f0) at /home/glorch/dev/ps/facebook-mysql/sql/mysqld.cc:7355
#15 0x000055555623085a in main (argc=5, argv=0x7fffffffd868) at /home/glorch/dev/ps/facebook-mysql/sql/main.cc:25

I don't feel this is a critical issue but reporting it in case there is a low-hanging way to address it without asserting.

[hermanlee]

Yes, it's the same issue. Could probably just extend the fix to check for use-direct-io-for-flush-and-compaction too.

[george-lorch]

Yup, I believe as well. I'll send in a patch in a bit.

[george-lorch]

#897