DB2 archive log extraordinary growth for any operation after runstat/reorg
Finally found what actually happen after 150GB in one day for archive log.
After doing offline runstat again, It seems that we ignore the "SQL2310N The utility could not generate statistics. error -930" on table RECONCILIATION_INFO

At first, we thought it might not be an important error but when we dig through db2diag.log, we found error 964 (transaction log full) as well during runstat however, we didn't found any error during reconcile in db2diag.log

So we increase LOGPRIMARY value to 25 (ISIM default is 13) and then, runstat work smoothly with a few GB increased in archive log. After that, reorg and runstat again didn't eat up space anymore.

We did some test by reconcile as usual and now disk space is not increase anymore.

I still wonder why runstat can cause a disk space problem like this even we just run it manually, restart database didn't help at all once we trigger it.