Details
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Bug
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Status: Closed (View Workflow)
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Major
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Resolution: Fixed
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10.3.1, 10.3(EOL), 10.4(EOL), 10.5
Description
This failure had been reported in MDEV-15533, which was filed about a different failure in 10.2.
There are multiple assertions log->blobs in the function row_log_table_apply_update(). The one that fails in the rr replay trace appears to be specific to 10.3 and later, likely caused by MDEV-12288:
if (memcmp(rec_trx_id, old_pk_trx_id->data, |
DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN)) {
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/* The ROW_T_UPDATE was logged for a different |
DB_TRX_ID,DB_ROLL_PTR. This is possible if an
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earlier ROW_T_INSERT or ROW_T_UPDATE was diverted
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because some BLOBs were missing due to rolling
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back the initial insert or due to purging
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the old BLOB values of an update. */
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ut_ad(log->blobs); |
In the trace that I analyzed, old_trx_id->data is reset_trx_id.
The value was assigned earlier:
#0 0x000055bd086d1405 in dfield_set_data (len=6,
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data=0x55bd0997f4e0 <reset_trx_id>, field=0x61200036ddb0)
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at /home/mleich/10.5_A/storage/innobase/include/data0data.ic:93
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#1 row_log_table_get_pk (rec=<optimized out>,
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index=index@entry=0x61800020f520, offsets=offsets@entry=0x7f9a4025f9d0,
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sys=sys@entry=0x0, heap=heap@entry=0x7f9a4025f6f0)
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at /home/mleich/10.5_A/storage/innobase/row/row0log.cc:1416
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#2 0x000055bd0876a3fd in row_upd_clust_rec (flags=flags@entry=0,
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node=node@entry=0x621000c6f220, index=index@entry=0x61800020f520,
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offsets=<optimized out>, offsets@entry=0x7f9a4025f9d0,
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offsets_heap=offsets_heap@entry=0x7f9a4025f850,
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thr=thr@entry=0x621000c6f600, mtr=<optimized out>)
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at /home/mleich/10.5_A/storage/innobase/row/row0upd.cc:2550
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The code in row_log_table_get_pk() is directly related to this:
if (trx_read_trx_id(trx_roll) < log->min_trx) { |
trx_roll = reset_trx_id;
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if (sys) { |
memcpy(sys, trx_roll, |
DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
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}
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...
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}
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ut_d(trx_id_check(trx_roll, log->min_trx)); |
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dfield_set_data(dtuple_get_nth_field(tuple, new_n_uniq),
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trx_roll, DATA_TRX_ID_LEN);
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dfield_set_data(dtuple_get_nth_field(tuple, new_n_uniq + 1),
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trx_roll + DATA_TRX_ID_LEN, DATA_ROLL_PTR_LEN);
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We should adjust the condition to take log->min_trx into account. At the time of the mismatch, we have mach_read_from_6(rec_trx_id) == 6388 and log->min_trx == 6385. It seems that we are correctly treating this as a mismatch of the DB_TRX_ID, because in row_log_table_get_pk() the original DB_TRX_ID must have been smaller than 6385. So, this might be a 'harmless' debug assertion failure.
This should only affect cases where the PRIMARY KEY is being redefined while concurrent DML is being executed. In the trace that I analyzed, ALTER TABLE t2 ADD PRIMARY KEY (col2) was being executed.
Attachments
Issue Links
- is caused by
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MDEV-13654 Various crashes due to DB_TRX_ID mismatch in table-rebuilding ALTER TABLE…LOCK=NONE
- Closed
- relates to
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MDEV-15533 Assertion `log->blobs' failed in row_log_table_apply_update
- Closed