xiaoyuyao commented on a change in pull request #1516: URL: https://github.com/apache/hadoop-ozone/pull/1516#discussion_r510363980
########## File path: hadoop-hdds/docs/content/feature/Quota.md ########## @@ -0,0 +1,67 @@ +--- +title: "Quota in Ozone" +date: "2020-October-22" +weight: 4 +summary: Quota in Ozone +icon: user +menu: + main: + parent: Features +summary: Introduction to Ozone Quota +--- +<!--- + Licensed to the Apache Software Foundation (ASF) under one or more + contributor license agreements. See the NOTICE file distributed with + this work for additional information regarding copyright ownership. + The ASF licenses this file to You under the Apache License, Version 2.0 + (the "License"); you may not use this file except in compliance with + the License. You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. +--> + +So far, we know that Ozone allows users to create volumes, buckets, and keys. A Volume usually contains several buckets, and each Bucket also contains a certain number of keys. Obviously, it should allow the user to define quotas (for example, how many buckets can be created under a Volume or how much space can be used by a Bucket), which is a common requirement for storage systems. + +## Currently supported +1. Storage Space level quota + +Administrators should be able to define how much storage space a Volume or Bucket can use. + +## Client usage +### Storage Space level quota +Storage space level quotas allow the use of units such as KB (k), MB (m), GB (g), TB (t), PB (p), etc. Represents how many storage Spaces will be used. + +#### Volume Storage Space level quota +```shell +bin/ozone sh volume create --space-quota 5m /volume1 +``` +This means setting the storage space of Volume1 to 5MB + +```shell +bin/ozone sh volume setquota --space-quota 10g /volume1 +``` +This behavior changes the quota of Volume1 to 10GB. + +#### Bucket Storage Space level quota +```shell +bin/ozone sh bucket create --space-quota 5m /volume1/bucket1 +``` +That means bucket1 allows us to use 5MB of storage. + +```shell +bin/ozone sh bucket setquota --space-quota 10g /volume1/bucket1 +``` +This behavior changes the quota for Bucket1 to 10GB + +A bucket quota should not be greater than its Volume quota. Let's look at an example. If we have a 10MB Volume and create five buckets under that Volume with a quota of 5MB, the total quota is 25MB. In this case, the bucket creation will always succeed, and we check the quota for bucket and volume when the data is actually written. Each write needs to check whether the current bucket is exceeding the limit and the current total volume usage is exceeding the limit. Review comment: what if the case of volume quota = 10MB but create a bucket of quota 20MB. Will the bucket create fail? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: ozone-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: ozone-issues-h...@hadoop.apache.org
