New Filesharing Implementation in Docker Desktop Windows Improves Developer Inner Loop UX

A common developer workflow when using frameworks like Symfony or React is to edit the source code u

A common developer workflow when using frameworks like Symfony or React is to edit the source code using a Windows IDE while running the app itself in a Docker container. The source is shared between the host and the container with a command like the following: This allows the developer to edit the source code, save the changes and immediately see the results in their browser. This is where file sharing performance becomes critical. The latest has using instead of Samba which: This improvement is available today in the and will roll-out to the stable channel later once we’ve had enough positive feedback. Please download it, give it a try and let us know how it goes.  If you discover any problems, please report them on and make sure you fill descriptions and reproduction steps so that we can quickly investigate. Performance is vital when application source code is being shared between the host and a container. For example when a developer uses the , edits the source code and then reloads the page in the browser, the web-server in the container must re-read many PHP files stored on the host. This must be fast. The following graph shows the time taken to load a page of a in three configurations: The two bars on the left hand side show the latency (in seconds) using an older version of Docker Desktop. Note that the second fetch is only slightly better than the first, suggesting that the effect of caching is small. The two bars on the right hand side show the latency when the files are not shared at all, but are stored entirely inside the VM. This is the upper limit on performance if the volume sharing system were perfect and had zero overheads. The two bars in the middle show the latency when the files are shared with the new system in Docker Desktop Edge 2.1.7.0. The initial (uncached) fetch is already better than with the previous Desktop version, but the second (cached) fetch is As well as big performance improvements, the new implementation has the following additional benefits: Stay tuned for a follow up post that deep dives into the new Docker Desktop filesharing implementation using FUSE.