Bug #50850 32-bit builds for IBM i should have maxdata increased
Submitted: 2 Feb 2010 19:19 Modified: 2 Dec 2010 13:25
Reporter: Tim Clark Email Updates:
Status: Won't fix Impact on me:
Category:MySQL Server: Compiling Severity:S3 (Non-critical)
Version:5.1.40, 5.1.43 OS:IBM i
Assigned to: CPU Architecture:Any

[2 Feb 2010 19:19] Tim Clark
Currently, MySQL builds for IBM i use the default maxdata configuration, which sets a limit on program storage (stack + heap) to 256 MB. Under heavy loads, the 32-bit build of MySQL can hit this limit, particularly when using the IBMDB2I storage engine. A larger maxdata value would provide more heap space and accomodate larger workloads.

How to repeat:
Use dump -o mysqld to examine the value of maxDATA:

> dump -o bin/mysqld                                                          
                          ***Object Module Header***                          
  # Sections      Symbol Ptr      # Symbols       Opt Hdr Len     Flags       
           7      0x01d8e578         707065                72     0x1002
  Timestamp = 1254928091                                                
  Magic = 0x1df                                                         
                          ***Optional Header***                         
  Tsize        Dsize       Bsize       Tstart      Dstart               
  0x0078516f  0x001edd45  0x00007034  0x10000178  0x200002e7            
  SNloader     SNentry     SNtext      SNtoc       SNdata               
  0x0004      0x0002      0x0001      0x0002      0x0002                
  TXTalign     DATAalign   TOC         vstamp      entry                
  0x0005      0x0003      0x201ea508  0x0001      0x201ba57c            
  maxSTACK     maxDATA     SNbss       magic       modtype              
  0x00000000  0x00000000  0x0003      0x010b    1L                                                                                                

Suggested fix:
Use -bmaxdata=0x80000000 for 32-bit builds of MySQL. See http://publib.boulder.ibm.com/infocenter/comphelp/v8v101/index.jsp?topic=/com.ibm.xlcpp8a....
[3 Feb 2010 7:01] Sveta Smirnova
Thank you for the report.

Verified as described.
[2 Dec 2010 13:25] Kent Boortz
Platform is not supported any more, see