The following sys schema views provide progress reporting for long-running transactions:

processlist
session
x$processlist
x$session

Assuming that the required instruments and consumers are enabled, the progress column of these views shows the percentage of work completed for stages that support progress reporting.

Stage progress reporting requires that the events_stages_current consumer be enabled, as well as the instruments for which progress information is desired. Instruments for these stages currently support progress reporting:

stage/sql/Copying to tmp table
stage/innodb/alter table (end)
stage/innodb/alter table (flush)
stage/innodb/alter table (insert)
stage/innodb/alter table (log apply index)
stage/innodb/alter table (log apply table)
stage/innodb/alter table (merge sort)
stage/innodb/alter table (read PK and internal sort)
stage/innodb/buffer pool load

For stages that do not support estimated and completed work reporting, or if the required instruments or consumers are not enabled, the progress column is NULL.