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In my case, I found the total size of S3 bucket was 180TB, but actually size I uploaded based on the origin storage was 40TB. I tried to compare all the files one by one, but haven't found any difference.
I learned AWS S3 keeps incomplete multipart uploads constantly and that won't be deleted as long as user does not do make any actions. This is something unusual architecture I haven't expected, so I paid for that incomplete multipart uploads, because people may expect the incomplete multi uploads would be deleted automatically as long as that parts are not integrated for very long time.
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