Deduplication among versions#
Minor container image updates#
Examine 10 versions of ubuntu:jammy from Docker Hub, specifically jammy-{20221130,20230126,20230301,20230308,20230425,20230522,20230605,20230624,20230804,20230816};
These images only have one layer which is in the tar.gz format;
Uncompressed EROFS images are built with
-Ededupeand compressed EROFS images are built with-Ededupe,all-fragmentsand LZ4HC, DEFLATE algorithms.
Total Size (MiB) |
Average layer size (MiB) |
Saved / 766.1MiB |
|
|---|---|---|---|
Compressed OCI (tar.gz) |
282.5 |
28.3 |
63% |
Uncompressed OCI (tar) |
766.1 |
76.6 |
0% |
Uncomprssed EROFS |
109.5 |
11.0 |
86% |
EROFS (DEFLATE,9,32k) |
46.4 |
4.6 |
94% |
EROFS (LZ4HC,12,64k) |
54.2 |
5.4 |
93% |
SquashFS (GZIP,9,128k,-noI [1]) |
47.0 |
4.7 |
94% |
SquashFS (LZ4HC,12,128k,-noI) |
54.7 |
5.5 |
93% |
It shows that EROFS gets smaller sizes even with smaller compression granularity.
Wikipedia snapshots#
Two snapshots were selected: 20230201
and 20230220:
Each snapshot included the first 100 pages at that time.
There was 20-day difference between each other.
Deduped? |
Size (MiB) |
Saved / 1888MiB |
|
|---|---|---|---|
Uncompressed text |
No |
1888 |
0% |
SquashFS [4k] [2] |
No |
1235 |
34.6% |
EROFS [4k, default] |
No |
1201 |
36.4% |
SquashFS [8k] |
No |
1150 |
39.1% |
EROFS [4k] [3] |
Yes |
1147 |
39.2% |
SquashFS [128k, default] |
No |
1110 |
41.2% |
EROFS [64k] |
Yes |
988 |
47.7% |
Linux kernel source code releases#
Three kernel releases are
selected: 5.10, 5.10.50, 5.10.100:
Images from both filesystems are compressed with
LZ4HC, 12since SquashFS uses the maximum level 12 for LZ4HC;EROFS images are built with
-T0 --force-uid=1000 --force-gid=100in order to force 32-byte inodes to approximately match SquashFS metadata size;
Fragments? |
Deduped? |
Size |
|
|---|---|---|---|
SquashFS [16k] |
Yes |
No |
409 MiB |
EROFS [4k, default] |
Yes |
Yes |
379 MiB |
SquashFS [32k] |
Yes |
No |
365 MiB |
EROFS [8k] |
Yes |
Yes |
347 MiB |
SquashFS [64k] |
Yes |
No |
334 MiB |
EROFS [32k] |
Yes |
Yes |
313 MiB |
SquashFS [128k, default] |
Yes |
No |
312 MiB |
EROFS [64k] |
Yes |
Yes |
310 MiB |