Low Auto Compression Ratio (1.06x)

Getting Help
1

Hello!

I’m looking for advice and / or help with respect to auto compression. My question is if this ratio (which seems low to me) is expected or abnormal.

My restic version is 0.17.3

I looked around the forum but didn’t find any direct comps to my question. I did see how to check my repo version and discover the compression ratio.

I confirmed I’m on repo version 2 with auto compression:

restic -r s3:s3.backblazeurl/bucketid cat config

repository xxx opened (version 2, compression level auto)
{
  "version": 2,
  "id": "xxx",
  "chunker_polynomial": "268e31e540c82b"
}

Then I grabbed the raw data stats

restic -r s3:s3.backblazeurl/bucketid stats --mode raw-data

repository xxx opened (version 2, compression level auto)
[0:00] 100.00%  62 / 62 index files loaded
scanning...
Stats in raw-data mode:
     Snapshots processed:  1
        Total Blob Count:  474231
 Total Uncompressed Size:  378.931 GiB
              Total Size:  356.320 GiB
    Compression Progress:  100.00%
       Compression Ratio:  1.06x
Compression Space Saving:  5.97%

This was my first backup (and my first time using restic). I suppose I could change the compression to max instead of auto, but given the very low ratio, I’m wondering if there’s something else I might look into in order to compress the data more.

This backup consists almost entirely of images (.jpg, .png, raw files) if that’s helpful context.

Thanks in advance for any help!

2

JPGs can’t be compressed any further using a lossless compression method as restic uses one. PNGs are usually already compressed as well. RAW files can be compressed but don’t have to be. My guess is that they are and that those 5.97% compression come from the rest of your files.

3

That makes sense! Thanks for the response.

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