mysqldump piped to gzip then s3 doesn't to run out of disk space

Question

I run the following command which all.sql.gz is greater than the amount of free space on hard drive....but somehow it completes without issue. Is it because of how the piping works?

mysqldump --defaults-file=/home/ec2-user/db-master.cnf --tz-utc=false --quick --all-databases --single-transaction --routines --triggers | gzip | s3cmd "$BACKUP_OPTIONS" put - "$BACKUP_S3PATH"/"php-pos-db"/"all".sql.gz >/dev/null 2>&1

score 1 · Answer 1 · answered Jan 02 '19 at 17:10

1

I don't see anything in your command that would result in any data being written to your hard drive at all. It's not surprising that it would not use any hard drive space, because it does not use any hard drive space.

answered Jan 02 '19 at 17:10

Michael Hampton

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Wouldn't it need a place to store the data or does it use memory? – Chris Muench Jan 02 '19 at 19:39
It looks like you're just sending the data to S3. All the commands in your pipeline are just operating in memory. – Michael Hampton Jan 02 '19 at 20:04

mysqldump piped to gzip then s3 doesn't to run out of disk space

1 Answers1