SHADOW_IMPORT_INC issue during EHP 7 upgrade
I have somce serious issues upgrading EHP 7 with my present environment in the Production system. I need help from someone who has experience in EHP 7 upgrade in Windows 2012 with SQL DB, most importantly eperience with SQL in an Availability group.
When we reached the SHADOW_IMPORT_INC phase in pre-processing, I noticed the perfomrance of the Upgrade was seriously low and thats when i got to see a Snote "1945399 - performance analysis for SHADOW_IMPORT_INC and TABIM_UPG phase" which suggest us to look at few areas such as DB Performance, SQL query, File system I/O, et. when i checked with the respective teams , i got a reponse saying that everything was normal.
But there is a sugestion from a DB team to remove the database from the availability group (both from DB level from the SAP parameter level) will help improve the performance of the Pre-processing phase, as the synchronization happens at both the ends of DB it may have caused the poor performance of the Shadow Import in the preprocessing.
we did check the Package import rate/duration from the SUM/ABAP/log and found an average difference of 25% between our Quality and Production. this means, the Quality server wsa 25% faster in Package Import then the Production System. Please note that the Qualityand the Production servers have same Hardware configuration. There are 2 differences we can think of between Test and Production.
1.Quality system was in SIMPLE mode when we started the Preprocessing in Test but the Production was not.
2.Availability group was not configured for Quality but it is configured in Production
ECC 6 EHP 6
SQL Server 2012 R2
thanks for the help in advance