Cache Setting Details
Cache Setting Details
Question
What do each of the Cache Settings mean? What effects come from changing each setting?
Answer
- Cache Files/Folder listings: Choose whether to store files and directory listings in cache or have them always be downloaded new (if disabling cache). Disabled cache ensures always updated items and GREATLY reduces performance as WebDrive and the server are constantly communicating and using resources to retrieve and redownload items.
- Clear cache when connecting: When connecting a site in WebDrive, this would have any stored cache cleared before initial connect.
- Limits are "soft" limits created to allow setting thresholds and maximum amounts of data for WebDrive to hold in cache at any one particular time. They are relatively self-explanatory, and here is some information:
- Limit total size of cached items: Maximum amount of space to be allowed to be held in Cache. One-time transfers of files larger than this size will still succeed, and items will be removed from the cache to get back under this limit as soon as possible.
- Limit number of files/folders in cache: A limit to the number of items held in cache at any one time. You may want to increase this if, for example, you have 6000 files in a folder. Increase the limit for cached files.
- NOTE: In the scenario presented above, it is HIGHLY recommended to instead reduce the size of each directory/folder. Having 6000 items in a folder is problematic for performance in several ways and generally not a recommended method for storing files that you want to retrieve and/or edit. The smaller the folders, the better
- For Cache Validation, the same is true for both files and folders (directory listings), with the difference being Files are files and directory listings are the listings of contents in each folder
- Compare cached item to server copy: This is the most efficient option if the server supports it. WebDrive will have files in its cache, and whenever a refresh is triggered, a file is opened, or a new folder is entered, etc. WebDrive will verify what it has that is relevant to that action with the server.
- Example: If a file is opened, WebDrive will check if that file is in cache. If it is not, it will download the file new. If it is in cache, it will see if the server has a newer version. If it does not, WebDrive will keep and open the cached version. If it does have a newer version, WebDrive will copy down the new version from the server and replace the old, cached file with the updated file.
- NOTE: This will work if the Minimum Validation Period has elapsed (set by the limit setting) -- x seconds or minutes to limit validation.
- Limiting validation means that WebDrive will only check for a new version of a file or folder listing every x seconds or x minutes, whatever this value is set to. This helps reduce unnecessary commands and traffic between WebDrive and the server. The higher the value, the longer WebDrive will wait before attempting to check if it should replace cached items.
- NOTE: If the Validation Time is set to 30 seconds, it could be 59/60 seconds before seeing an update made by another user. This is because a Validation period may have just happened, and then the polling is not done for a while afterwards, and then they are made stale, and then the refresh happens when the user requests a refresh. Think of doubling the Validation/Expiration time and that is around the maximum wait time to see updates.
- Consider Cached items stale based on time: WebDrive will consider cached items "stale" or "old" after x seconds or x minutes. This is less efficient, but sometimes necessary depending on the server capabilities or user desires. This means that after x seconds, all items in the cache will be considered out of date. The next time that listing or file or other cached item is considered, it will be thrown out and a new copy will be downloaded.
- Example: If there are 400 files inside of a folder, and this listing is cached. Even if none of these items have changed, if the elapsed time has passed and the user refreshes Windows Explorer or navigates back into this folder, the entire directory listing would be thrown out and re-downloaded. This results in a lot of excess traffic between WebDrive and the server. Expiration of cache, or disabling cache entirely, are often the reasons for poor performance or lags or long waits between actions, or even throttling by the server itself. Another reason for poor performance or throttling would be unwieldly-sized folders with thousands and thousands of files in them.
- Never would suggest that only one user accesses these files or that users would manually flush cache to retrieve updates. Minimal effort for WebDrive and the server communication, but more work for the user to manually check for new items by flushing the cache in WebDrive. Used in some automation cases, single user use cases, and other one-offs.
- Update changed files in background is whether WebDrive will attempt to update files even without a refresh of Explorer or other apps. This causes more strain on the system as well, as WebDrive polls on an interval to try to update live (even if user did not perform an action or request a refresh).