Details
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Bug
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Status: Done
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Medium
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Resolution: Fixed
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5.7.24-26
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None
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Tested with Percona Server 5.7.24 and 5.7.25
Description
This is regarding the following functionality:
https://www.percona.com/doc/percona-server/5.7/management/changed_page_tracking.html
When we enable innodb_track_changed_pages, we see the following error messages after some writes:
2019-04-01T23:03:54.355418Z 2 [ERROR] InnoDB: Encryption algorithm support missing: N 2019-04-01T23:03:54.356065Z 2 [ERROR] InnoDB: Encryption algorithm support missing: N
The attached files can be run in an environment where dbdeployer is available, to reproduce it 100% of the times). Run them in the following way (they should be in the ~/sandboxes/ directory):
shell> bash track_changed_pages.sh track_changed_pages_int.sql shell> bash track_changed_pages.sh track_changed_pages_uuid.sql
The innodb_max_bitmap_file_size doesn't seem to be relevant to the amount of times we see the errors shown above.
While checking this deeper, I noted the following.
After checking the source code, I noted this error is only printed in storage/innobase/os/os0file.cc:
[email protected] /opt/percona_server/src/5.7.24-26 $ grep "Encryption algo" storage/innobase/os/os0file.cc << "Encryption algorithm support missing: " << "Encryption algorithm support missing: " fprintf(stderr, "Encryption algorithm support missing: %s\n",
In particular in the Encryption::decrypt_log_block() and Encryption::decrypt() functions.
I attached gdb to the running sandbox process, set breakpoints on these functions, and run the query again, and got the following results:
(gdb) b Encryption::decrypt_log_block Breakpoint 1 at 0x10645e0: file /mnt/workspace/percona-server-5.7-binaries-release-rocks-new/label_exp/min-centos-6-x64/test/percona-server-5.7.24-26/storage/innobase/os/os0file.cc, line 10553. (gdb) b Encryption::decrypt Breakpoint 2 at 0x1064b00: file /mnt/workspace/percona-server-5.7-binaries-release-rocks-new/label_exp/min-centos-6-x64/test/percona-server-5.7.24-26/storage/innobase/os/os0file.cc, line 10731. (gdb) c Continuing. [Switching to Thread 0x7f8c31e25700 (LWP 35976)] Breakpoint 1, Encryption::decrypt_log_block (this=this@entry=0x7f8c31e215d0, type=..., [email protected]=0x7f8818c4c218 '�' <repeats 135 times>, "\037", [email protected]=0x7f8c26f3a018 "") at /mnt/workspace/percona-server-5.7-binaries-release-rocks-new/label_exp/min-centos-6-x64/test/percona-server-5.7.24-26/ storage/innobase/os/os0file.cc:10553 10553 /mnt/workspace/percona-server-5.7-binaries-release-rocks-new/label_exp/min-centos-6-x64/test/percona-server-5.7.24-26/storage/innobase/os/os0file.cc: No such file or directory. (gdb) p m_type $1 = Encryption::NONE
This is triggering the following codepath:
10542 /** Decrypt the log block. 10543 @param[in] type IORequest 10544 @param[in,out] src Data read from disk, decrypted data will be 10545 copied to this page 10546 @param[in,out] dst Scratch area to use for decryption 10547 @return DB_SUCCESS or error code */ 10548 dberr_t 10549 Encryption::decrypt_log_block( 10550 const IORequest& type, 10551 byte* src, 10552 byte* dst) 10553 { ... 10561 switch (m_type) { 10562 case Encryption::AES: { ... 10621 default: 10622 ib::error() 10623 << "Encryption algorithm support missing: " 10624 << Encryption::to_string(m_type); 10625 return(DB_UNSUPPORTED); 10626 } ...
As we can see there, it only supports the AES encryption, but these pages have NONE, making the thread fail with that error. The "N" we see in the error log is due to this ("NONE").
All these outputs are for version 5.7.24. I run the tests on 5.7.25, too, and it's still reproducible.
This is the farthest I could go here 
After this I'm a bit lost. I hope this is enough to help get more insight into these issues.
