examples/dedupe-global.fio

# Writing to 2 files that share the duplicate blocks.
# The dedupe working set is spread uniformly such that when
# each of the jobs choose to perform a dedup operation they will
# regenerate a buffer from the global space.
# If you test the dedup ratio on either file by itself the result
# is likely lower than if you test the ratio of the two files combined.
#
# Use `./t/fio-dedupe <file> -C 1 -c 1 -b 4096` to test the total
# data reduction ratio.
#
#
# Full example of test:
# $ ./fio ./examples/dedupe-global.fio
#
# Checking ratio on a and b individually:
# $ ./t/fio-dedupe a.0.0 -C 1 -c 1 -b 4096
#
# $ Extents=25600, Unique extents=16817 Duplicated extents=5735
# $ De-dupe ratio: 1:0.52
# $ De-dupe working set at least: 22.40%
# $ Fio setting: dedupe_percentage=34
# $ Unique capacity 33MB
#
# ./t/fio-dedupe b.0.0 -C 1 -c 1 -b 4096
# $ Extents=25600, Unique extents=17009 Duplicated extents=5636
# $ De-dupe ratio: 1:0.51
# $ De-dupe working set at least: 22.02%
# $ Fio setting: dedupe_percentage=34
# $ Unique capacity 34MB
#
# Combining files:
# $ cat a.0.0 > c.0.0
# $ cat b.0.0 >> c.0.0
#
# Checking data reduction ratio on combined file:
# $ ./t/fio-dedupe c.0.0 -C 1 -c 1 -b 4096
# $ Extents=51200, Unique extents=25747 Duplicated extents=11028
# $ De-dupe ratio: 1:0.99
# $ De-dupe working set at least: 21.54%
# $ Fio setting: dedupe_percentage=50
# $ Unique capacity 51MB
#
[global]
ioengine=libaio
iodepth=256
size=100m
dedupe_mode=working_set
dedupe_global=1
dedupe_percentage=50
blocksize=4k
rw=write
buffer_compress_percentage=50
dedupe_working_set_percentage=50

[a]

[b]