Skip to main content

New Burst Protection Algorithm

To protect users against surprise charges, FeedMail covers the cost of sudden bursts of updates. The initial algorithm, only charging once a day, was too simple. Many feeds regularly see multiple updates a day and the burst-protection algorithm was artificially subsidizing these feeds.

FeedMail is now using an updated algorithm to protect from bursts. The exact implementation is subject to change but is based on the following principles:

  • Updates more than 24h apart are almost always charged.
  • An average update rate is tracked per-feed. If a feed suddenly starts updating faster than the traditional rate the additional updates will not be charged.
  • The average is updated over time, so if a feed continues updating at the elevated rate credit consumption will slowly increase to match the new update rate.

FeedMail aims to be very low cost. To achieve this we need to keep our expenses predictable and fair. Otherwise we would need to overcharge some users to cover uncertainty and higher cost users.

To be fair to users who have purchased credits with the previous expectation in mind existing paid users will have their credit balance doubled to account for this difference. Based on our analysis this means that the remaining balance will last longer for all existing users. If any paid users feel like this will reduce the value of their credits please reach out to our support team and we will find the fair adjustment.


Popular posts from this blog

Delivery Delays to Gmail

In the past 48 hours Google has started delaying the delivery of some FeedMail notifications. This is currently affecting about 10% of messages to Gmail users. These notifications will be resent with a delay. We also speculate that some notifications will be marked as spam.   Update : As of 2023-05-09 this appears to be resolved. If You Are Affected If you use Gmail you may be affected by this. Notifications may be delayed or marked as spam. If your notifications are marked as spam you can create a filter to avoid this. Use "from:*" as the rule and select " Never send it to Spam". If your notifications are delayed we are unaware of any action that you can take. However marking notifications that ended up in your spam folder as "Not Spam" may help avoid future delays.  It does appear that these emails are eventually being accepted but we are unsure if that means that they are actually ending up in users' mailboxes (or even their spam folder

Updates to HTML Processing

Since its inception FeedMail has done processing on HTML content in feeds to ensure that it renders as expected in email form. At first this was fairly simple things like rewriting URLs to point to the correct location (many feeds use non-absolute URLs that won't work in email) but over time more complex transformations were added such as adding fallback content to media embeds without any. The full-text scraping feature requires even more complex processing as it requires stripping away most of the page and handling content that was designed for full-featured browsers. What changed? Recently FeedMail has migrated all HTML rewriting to use new infrastructure. This provides more flexibility and enabled new features (such as showing controls on all media embeds) and made our processing much more reliable. What does this mean to me? As a user you shouldn't see much difference. Overall the emails you receive should be better formatted but the difference will be subtle. Full-text sc

Email Headers

FeedMail now sets some email headers that advanced users can use to filter the messages that FeedMail sends. For example you can filter notifications in a specific category into a different folder. The headers that we set are documented in the FAQ . These headers have been being set on notifications for a few months now so you can use past messages to test your filters. If you have any questions, or would like to see other headers set to help your filtering please let us know .