st: memory required for -merge-

[Danielle H Ferry <dferry@nber.org>]

Hi all,

Is there a rule for the amount of memory required for -merge-? I keep  
getting a "no room to add more variables due to width" error on the  
same merge. I am attempting to -merge- on only one variable  
(placefip), and 67% of memory is free before I attempt the -merge-  
(i.e., while the "master" dataset is loaded). The "using dataset is  
small, and I've got the memory set quite high (900m). So, I can't  
understand why I am running into memory problems.

This is the info on the "master" dataset:

. des

Contains data from ../data/geog/geog_pooled.dta
  obs:    20,873,141
vars:             4                          8 Mar 2006 21:32
size:   333,970,256 (66.5% of memory free)   (_dta has notes)
------------------------------------------------------------------------ 
-------
              storage  display     value
variable name   type   format      label      variable label
------------------------------------------------------------------------ 
-------
cityres         long   %05.0f               * City of residence
msarfip         int    %04.0f               * PMSA/MSA of residence  
(FIPS)
year            int    %4.0g
placefip        long   %07.0f               * Place (city) of  
residence (FIPS)
                                            * indicated variables  
have notes
------------------------------------------------------------------------ 
-------

And this is the info on the "using" dataset:

. des using ../data/geog/geog_cc

Contains data
  obs:        25,150                          8 Mar 2006 22:21
vars:             3
size:     1,207,200
------------------------------------------------------------------------ 
-------
              storage  display     value
variable name   type   format      label      variable label
------------------------------------------------------------------------ 
-------
macci           byte   %1.0g                  Center city
placefip        long   %07.0f
place_name      str39  %39s
------------------------------------------------------------------------ 
-------
Sorted by:  placefip

 This is the memory usage I see after the error, when the "master"  
dataset is loaded:

. memory
                                                  bytes
--------------------------------------------------------------------
Details of set memory usage
    overhead (pointers)                      83,492,564        8.38%
    data                                    250,477,692       25.14%
                                        ----------------------------
    data + overhead                         333,970,256       33.53%
    free                                    662,176,944       66.47%
                                        ----------------------------
    Total allocated                         996,147,200      100.00%
--------------------------------------------------------------------
Other memory usage
    set maxvar usage                          1,848,666
    set matsize usage                         1,315,200
    programs, saved results, etc.                41,128
                                        ---------------
    Total                                     3,204,994
-------------------------------------------------------
Grand total                                 999,352,194

Any ideas?

--
Danielle H Ferry


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