Details
-
Bug
-
Status: Resolved (View Workflow)
-
Minor
-
Resolution: Fixed
-
Master:
openjdk version "1.8.0_66-internal"
OpenJDK Runtime Environment (build 1.8.0_66-internal-b01)
OpenJDK 64-Bit Server VM (build 25.66-b01, mixed mode)
Slaves:
java version "1.7.0_111"
OpenJDK Runtime Environment (IcedTea 2.6.7) (7u111-2.6.7-0ubuntu0.14.04.3)
OpenJDK 64-Bit Server VM (build 24.111-b01, mixed mode)
Master: openjdk version "1.8.0_66-internal" OpenJDK Runtime Environment (build 1.8.0_66-internal-b01) OpenJDK 64-Bit Server VM (build 25.66-b01, mixed mode) Slaves: java version "1.7.0_111" OpenJDK Runtime Environment (IcedTea 2.6.7) (7u111-2.6.7-0ubuntu0.14.04.3) OpenJDK 64-Bit Server VM (build 24.111-b01, mixed mode)
Description
When sending a stash across the network, the data transfer can be significantly slower than the underlying network. This seems to be due to some slow on-the-fly compression happening during the transfer. Using the following script, the Unstash phase takes 1-2 seconds for 10MB of /dev/zero, and 49 seconds for 10MB of /dev/urandom. The Stash phase consistently takes 1-2 seconds. This makes me think there's a compression step, since /dev/zero should compress much faster than /dev/urandom.
node {
deleteDir()
stage "Stash"
sh "dd if=/dev/zero of=data bs=1M count=10"
stash name: 'build_outputs', includes: 'data'
sh "date"
node('lab') {
deleteDir()
stage "Unstash"
unstash 'build_outputs'
sh "ls -al"
}
}
This looks similar to JENKINS-36914, in particular this comment:
https://issues.jenkins-ci.org/browse/JENKINS-36914?focusedCommentId=268472&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-268472
I'm not calling this a dupe of that because the original text refers to stash only, and this bug seems isolated to unstash. Also this is on x86, not ARM.
Attachments
Issue Links
- is duplicated by
-
-
- Closed
-
- is related to
-
-
- Resolved
-
- links to
Activity
Code changed in jenkins
User: Andres Rodriguez
Path:
src/main/java/org/jenkinsci/plugins/workflow/flow/StashManager.java
http://jenkins-ci.org/commit/workflow-api-plugin/5b4c7552511fe503cf4a5278b3de3c117cb25e0e
Log:
JENKINS-38640 Use a GREEDY RemoteInputStream
Code changed in jenkins
User: Jesse Glick
Path:
src/main/java/org/jenkinsci/plugins/workflow/flow/StashManager.java
http://jenkins-ci.org/commit/workflow-api-plugin/ca8f6dd3537dcb866e0aa02957ff80e702593884
Log:
Merge pull request #19 from andresrc/JENKINS-38640
JENKINS-38640 Use a GREEDY RemoteInputStream
Compare: https://github.com/jenkinsci/workflow-api-plugin/compare/42a296e511f8...ca8f6dd3537d
Code changed in jenkins
User: Jesse Glick
Path:
src/main/resources/org/jenkinsci/plugins/workflow/support/steps/stash/StashStep/help.html
http://jenkins-ci.org/commit/workflow-basic-steps-plugin/413df48bdcb832261e8fb110150eeb8069e77c33
Log:
JENKINS-38640 JENKINS-36914 Warn users to avoid stash/unstash of large files
John Koleszar
added a comment - Thanks for the workaround. It won't help in my application, as the master can only initiate connections to the slaves via ssh, and no connections can be initiated in the other direction. A shared filesystem via NFS or similar isn't really practical, unfortunately. Stash does what I want, and I'm willing to take some performance hit, but it should be able to do much better than 200KB/s on this hardware. Looking forward to trying out the greedy change to see how that does.
John Koleszar
added a comment - Thanks for the workaround. It won't help in my application, as the master can only initiate connections to the slaves via ssh, and no connections can be initiated in the other direction. A shared filesystem via NFS or similar isn't really practical, unfortunately. Stash does what I want, and I'm willing to take some performance hit, but it should be able to do much better than 200KB/s on this hardware. Looking forward to trying out the greedy change to see how that does. Code changed in jenkins
User: Jesse Glick
Path:
src/main/resources/org/jenkinsci/plugins/workflow/support/steps/stash/StashStep/help.html
http://jenkins-ci.org/commit/workflow-basic-steps-plugin/f541cd2cda5f316042d38af556f4160f7e470ccf
Log:
Merge pull request #23 from jenkinsci/jglick-stash-docs
JENKINS-38640 JENKINS-36914 Warn users to avoid stash/unstash of large files
Compare: https://github.com/jenkinsci/workflow-basic-steps-plugin/compare/95e202bec553...f541cd2cda5f
Sean Flanigan
added a comment - The External Workspace Manager plugin seems to require sharing drives between master and slaves, which rules it out in a lot of situations.
If, instead of stashing, the official recommendation is to use an external repository manager such as Nexus or Artifactory, it would be good to have some pipeline examples. For instance, how to stash the majority of workspace files, whilst letting the repository manager handle the larger files, and still ensuring that the right files are used together throughout the pipeline.
Sean Flanigan
added a comment - The External Workspace Manager plugin seems to require sharing drives between master and slaves, which rules it out in a lot of situations.
If, instead of stashing, the official recommendation is to use an external repository manager such as Nexus or Artifactory, it would be good to have some pipeline examples. For instance, how to stash the majority of workspace files, whilst letting the repository manager handle the larger files, and still ensuring that the right files are used together throughout the pipeline. John Koleszar
added a comment - The admonition not to use stash is too strong, in my opinion. I can see plenty of situations where having a repository manager or setting up shared storage are completely unnecessary complexity. The latest release of this plugin performs as I'd expect.
John Koleszar
added a comment - The admonition not to use stash is too strong, in my opinion. I can see plenty of situations where having a repository manager or setting up shared storage are completely unnecessary complexity. The latest release of this plugin performs as I'd expect. There is NO official recommendation to avoid stash/unstash. I've just mentioned it as a possible workaround
John Koleszar
added a comment - Thanks, Oleg. This is the documentation I was referring to about stash only being suitable for small files:
https://github.com/jenkinsci/workflow-basic-steps-plugin/commit/413df48bdcb832261e8fb110150eeb8069e77c33
Maybe there's an upper limit where it falls over, but I haven't hit it yet. In my opinion, if there were one, it'd be a bug worth fixing, rather than something to document away as WAI.
John Koleszar
added a comment - Thanks, Oleg. This is the documentation I was referring to about stash only being suitable for small files:
https://github.com/jenkinsci/workflow-basic-steps-plugin/commit/413df48bdcb832261e8fb110150eeb8069e77c33
Maybe there's an upper limit where it falls over, but I haven't hit it yet. In my opinion, if there were one, it'd be a bug worth fixing, rather than something to document away as WAI. 
External Workspace Manager (https://github.com/jenkinsci/external-workspace-manager-plugin/blob/master/README.md) could be a workaround. With this plugin you can share the entire workspace on filer instead of stashing particular files and getting overhead on the Jenkins side.