Some suggestions to try:

Use Locate by itself instead of go top
Use Scan/Endscan instead of do while ! eof()

Just a couple of quick things to try.

>Hello,
>
>I used to run the following lines of codes in FPW 2.6 , it took less than 1 minute to complete the process but with VFP7 it's more than 8 minutes for the same data range , please help me to identify the causes of slow process.
>
>Thanks in advance,
>PP
>
>set strictdate to 0
>select tmpperf
>go top
>do while !eof()
> select CUSTWAIT
> go top
> store 0 to stand1, sample1, stdm, smpm,stdy,smpy
> do while !eof()
> if airport=tmpperf.airport and carrier=tmpperf.carrier and loc_code = alltrim(tmpperf.cfield1)
> stand1=stand1+iif(m_stand='P'and event_date >=m.from,1,0)
> sample1=sample1+iif(m_stand#'-' and event_date >=m.from,1,0)
> stdm=stdm+iif(m_stand='P' and event_date >= m.prev_month,1,0)
> smpm=smpm+iif(m_stand#'-' and event_date >= m.prev_month,1,0)
> stdy=stdy+iif(m_stand='P' and event_date >= m.prev_year,1,0)
> smpy=smpy+iif(m_stand#'-' and event_date >= m.prev_year,1,0)
> endif
> skip
> enddo
> select tmpperf
> replace cfield2 with allt(str(sample1)),cfield3 with pct(stand1,sample1),;
> cfield4 with pct(stdm,smpm),cfield5 with pct(stdy,smpy),;
> cfield1 with iif(seek(allt(tmpperf.cfield1),"QTLOCAT"),QTLOCAT.NAME,"??????")
> skip
>enddo