Why is your WeChat getting bigger and bigger?

Students who use WeChat know that if WeChat is not cleaned up, the space occupied by it will gradually increase from 1GB to 10GB, 50GB or even larger, as shown in the following figure:

Some students have questions. Doesn’t WeChat clean up pictures, videos and files regularly?

WeChat will regularly clean up pictures, videos and files that are older than a certain time, and pictures, videos and files take up the most space. Why is WeChat getting bigger and bigger?

Because pictures, videos and files are "temporarily" stored on WeChat servers. If users do not download them for viewing, they are not downloaded and do not take up space on their phones. Only thumbnail data is stored, and the amount of thumbnail data is very small.

When a certain time has passed, the WeChat server will delete the pictures, videos and files received by the user, making them unable to be downloaded and viewed normally. This process will not reduce the space occupied by WeChat.

Can’t WeChat have a regular cleanup mechanism to prevent it from getting bigger and bigger? Next, let’s decipher this question. The outline of this article is as follows:

• WeChat storage mechanism
• WeChat cleanup mechanism
• Is there a solution?

1. WeChat storage mechanism

According to WeChat's official statement, WeChat does not upload user chat information to the cloud, and chat records are actually stored locally on the phone.

Why does WeChat use local storage mechanism?

WeChat promotes that local storage rather than cloud storage can more safely protect user privacy. If WeChat wants to better protect user privacy, can it use encryption to protect it instead of storing it locally?

When receiving a message from another user, if it is a picture or video, WeChat will first store the thumbnail, as shown in Figure 1 below.

Assume that the thumbnail size is 5k, the large image size is 30k, and the original image size is 105k.

If another group member posts this picture and the user does not click to view it, it will be stored as 5k. If the user clicks to view the larger picture, it will be stored as 30k. If the user clicks to view the original picture, it will be stored as 105k.

The same goes for videos.

As for files, once downloaded, they will always be stored in the phone and will not be cleaned up.

If the file is not downloaded, it will be stored in WeChat's server for a short period of time. After a certain period of time, the server data will be deleted and the user will not be able to download it. As shown in the figure below.

Although WeChat cannot be said to be on the cloud, it needs to be on the cloud in the short term, otherwise it cannot be used normally.

2. WeChat cleanup mechanism

Now that we know the storage mechanism of WeChat, let's take a look at the WeChat server cleanup mechanism.

When a certain time has passed, the WeChat server will delete the pictures, videos and files that the user has not clicked to view, so the user will not be able to download them.

So there are three reasons why WeChat is getting bigger and bigger:

• The pictures, videos and files sent by users themselves will not be cleaned up regularly, which leads to an increasing amount of space occupied.
• If the user clicks on a large image or the original image (video), the image (video) will not be cleaned up no matter how long it has been. WeChat also tries to save as many valuable files as possible.
• If the file has been downloaded by the user, it will not be cleaned up no matter how long it has been.

The above three points are the reasons why WeChat will occupy more and more space.

3. Is there a solution?

Many people online complain about WeChat taking up a lot of space on their phones, so is there a better solution?

I think the best solution is to upload data to the cloud and encrypt it. All local storage should be completely cleared of data older than a certain period of time (including data sent and downloaded by users themselves). If users want to view data, they can download it again from the cloud. In this way, the space occupied by WeChat will not be too large.

There is a problem with doing this, which is that the server costs of WeChat will be very high, but a method similar to QQ member roaming can be used to reduce operating costs.

When there are restrictions on local data storage, there is no better solution.

WeChat’s logic of local storage and cleanup is theoretically good enough. If there were a better solution, WeChat’s product managers would have done it long ago.