Lvarchar and dbimport

A customer has migrated from IDS 9.2 to IDS 9.4, changing machines en-route. They used dbexport from 9.2 and dbimport in 9.4. They migrated 1.5Gbyte database in IDS 9.2 and it became 8.5Gbyte in IDS 9.4. Further investigation has revealed that particular tables have increased in size dramatically. All of these tables have lvarchar columns, and the worst offender has 2 of them. Further investigation has revealed that the dbexport was not done with -ss option, so I had expected to find default extent sizes for the tables. However it appears that dbimport is now setting appropriate extent sizes in version 9.4 and that it gets the calculation wrong when lvarchar is used. These are the details of two of the tables found from sysmaster tables. table 1 table 2 ti_nptotal 1,513,374 1,174,570 ti_npused 74,875 367,754 ti_nrows 739,182 2,795,364 ti_rowsize 4,166 2,349 table 1 uses 2 lvarchars of length 2048 and table 2 uses 1 lvarchar. I am trying to report this problem to IBM/Informix tech support but hitting problems due to uncertainties about the revenue getting from customer to VAR to distributor to IBM. Looks like this could be one of the causes of size increase when migrating to 9.4 regards Malcolm

malcolm wrote: > A customer has migrated from IDS 9.2 to IDS 9.4, changing machines > en-route. They used dbexport from 9.2 and dbimport in 9.4. They > migrated 1.5Gbyte database in IDS 9.2 and it became 8.5Gbyte in IDS > 9.4. Further investigation has revealed that particular tables have > increased in size dramatically. All of these tables have lvarchar > columns, and the worst offender has 2 of them. > > Further investigation has revealed that the dbexport was not done with > -ss option, so I had expected to find default extent sizes for the > tables. However it appears that dbimport is now setting appropriate > extent sizes in version 9.4 and that it gets the calculation wrong > when lvarchar is used. > > These are the details of two of the tables found from sysmaster > tables. > > table 1 table 2 > ti_nptotal 1,513,374 1,174,570 > ti_npused 74,875 367,754 > ti_nrows 739,182 2,795,364 > ti_rowsize 4,166 2,349 > > table 1 uses 2 lvarchars of length 2048 and table 2 uses 1 lvarchar. > > I am trying to report this problem to IBM/Informix tech support but > hitting problems due to uncertainties about the revenue getting from > customer to VAR to distributor to IBM. > > Looks like this could be one of the causes of size increase when > migrating to 9.4 > > regards > > Malcolm What would be a bit more informative would be : oncheck -pt for the tables oncheck -pe for the dbspaces where the tables' data resides Would be interesting to see the extent allocation, and whether there was contiguous space available or not.