SAP on IBM i – Lock Issues on SQL Packages with Kernel Release 7.49 Resolved
SAP kernel release 7.49 has been released as a downward-compatible kernel for all SAP NetWeaver releases 7.40 and higher in December 2016. We talked about this in more detail in an earlier blog post and pointed out also that this kernel release includes significant improvements in the way we communicate with Db2 for IBM i. One of those features circles around the revamped handling of SQL packages and the way how SQL statements get distributed across them. As an effect of that, identification and reuse of SQL statements got much more efficient in many cases. Another benefit is that big SQL packages will practically not overflow anymore, while contents of multiple very small SQL packages get bundled in fewer midsize packages.
Those and other features should make kernel release 7.49 attractive to use. Unfortunately, some early adopters experienced dramatic system hang situations sometime after the switch. IBM quickly released a set of PTFs that alleviates the problem. Meanwhile we have also understood the root cause and released SAP patches for it that make the PTFs superfluous:
- 7.49 LIB_DBSL patch level 414
- 7.53 LIB_DBSL patch level 090
More details can be found in SAP Note 2581617 – “DB4: SQL-913 Locks on SQL Packages in the 749 Kernel”. As a side effect of this, we now know that the new SQL package handling is robust enough to survive crazy stress tests, which makes us very confident and relaxed with respect to its quality. We hope you will enjoy it, too!