(Import) equation for buffer value & server memory

In import there is parameter buffer

The value u can give to several MB's

but it also depends upon the OS MEMORY ALSO,

I want to know the equation

For how much memory availabe in OS how much buffer value can be given?

HOW TO FIND OUT THAT

now example - suppose the database server is having 1 Gb memory and i want to do import, what buffer value i can give to maximum

Gajanan

Docs are a good thing

BUFFER
Default: operating system-dependent

The integer specified for BUFFER is the size, in bytes, of the buffer through which data rows are transferred.

BUFFER determines the number of rows in the array inserted by Import. The following formula gives an approximation of the buffer size that inserts a given array of rows:

buffer_size = rows_in_array * maximum_row_size


For tables containing LONG, LOB, BFILE, REF, ROWID, UROWID, or DATE columns, rows are inserted individually. The size of the buffer must be large enough to contain the entire row, except for LOB and LONG columns. If the buffer cannot hold the longest row in a table, Import attempts to allocate a larger buffer

My KISS standard is...

BUFFER=12000000
COMMIT=y

Never fails.