PXB-3302: GTID of the last change output truncated in Xtrabackup back… #1576
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…up log https://perconadev.atlassian.net/browse/PXB-3302 Problem: -------- If the number of GTID sets are absolutely large on a MySQL instance, the output “GTID of the last change” in the Xtrabackup log is truncated compared to the full output in xtrabackup_binlog_info and xtrabackup_info Analysis: --------- The new error logging framework had limitation of 8192 characters and anything above is truncated. A string buf is formed and later passed to default implementaion of error logging. log_write_errstream(). See log_sink_trad(): if (output_buffer != nullptr) { if (msg_len < output_buffer->data.data_buffer.length) output_buffer->data.data_buffer.length = msg_len; else // truncate message to buffer-size (and leave space for '\0') msg_len = output_buffer->data.data_buffer.length - 1; Fix: ---- Since xtrabackup dont use any other configurable loggers, we can avoid this output_buffer, and directly log to stderr.
aybek
approved these changes
Jul 1, 2024
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…up log
https://perconadev.atlassian.net/browse/PXB-3302
Problem:
If the number of GTID sets are absolutely large on a MySQL instance, the output “GTID of the last change” in the Xtrabackup log is truncated compared to the full output in xtrabackup_binlog_info and xtrabackup_info
Analysis:
The new error logging framework had limitation of 8192 characters and anything above is truncated.
A string buf is formed and later passed to default implementaion of error logging. log_write_errstream().
See log_sink_trad():
if (output_buffer != nullptr) {
if (msg_len < output_buffer->data.data_buffer.length)
output_buffer->data.data_buffer.length = msg_len;
else // truncate message to buffer-size (and leave space for '\0')
msg_len = output_buffer->data.data_buffer.length - 1;
Fix:
Since xtrabackup dont use any other configurable loggers, we can avoid this output_buffer, and directly log to stderr.