There is no way I know of to get the number of inputs records from the input
unless you only write 100 to the input file.
Might find better help on this from the hadoop user group they know the MR
framework better then me.
Billy
"ma qiang" <[EMAIL PROTECTED]> wrote in
message news:[EMAIL PROTECTED]
Thanks very much.
However, I want to use the number of the map in my program. for
example. There are 100 map in a map task, and I want to collect all
the values, and analyze these values then output the last result in
the last map.
generally, there is no ouput in the first 99 map, only output exists
in the last map.
So I should know how many map in a map task.
On Mon, Nov 10, 2008 at 4:33 PM, Billy Pearson
<[EMAIL PROTECTED]> wrote:
If you are using TableMap to read the data back each mapper will map over
all the rows in a single region.
You can use counters to count the records so we can get a total records.
but there is not set number of maps a mapper will process it depends on
the
input.
Billy
"ma qiang" <[EMAIL PROTECTED]> wrote in
message
news:[EMAIL PROTECTED]
hi all,
I hava a data set stored in hbase, and I run a mapreduce program
to analyze. Now I want to know how many map in a map task? Who can
tell me?
Thanks a lot.
yours qiang.
