*as of December 2016
And since one of the important and popular issues for ordinary users of IT industry products was and remains the issue of device memory , this topic did not bypass the operating system from Google . Below we will discuss this topic and answer the question what types of memory are there in the Android OS system .
Grouping device memory types
First, let's look at what types of memory exist in principle. This grouping does not depend on the operating system used on the device, be it Android , Windows , MacOS , iOS , Linux or other less common platforms.
All storage devices in electronics can be divided into two main groups:
- Volatile memory. RAM
- Non-volatile memory. ROM
It’s clear with non-volatile memory, we designated it as RAM (Random Access Memory). But to call all non-volatile memory as ROM is a rough assumption, since ROM is Read-Only Memory, that is, it allows only reading, but the group of non-volatile memory also includes devices that allow the user to overwrite data. However, we will allow ourselves this generalization, and later we will briefly note the features of various ROM memory groups.
only RAM can be distinguished from the type of volatile memory in Android non-volatile memory , in turn, is divided into various sections: the system partition (which itself is also divided into sections), the internal memory of the device (Internal storage), flash memory ( memory card).
We'll talk about this below. In the meantime, here is a table showing which group each of the types of memory found on modern Android smartphones belongs to, with the most commonly used designations. Types of memory in Android system
| Volatile memory. RAM | RAM. RAM | ||
| Non-volatile memory. ROM | Section to be stitched. PROM | Bootloader | |
| Recovery | |||
| Boot | |||
| System | |||
| Writable partition. EEPROM | Internal phone storage | Data | |
| User | |||
| SD card | |||
At the end of the article, we will provide another table in which we will very roughly try to compare the considered sections of the Android system and the sections/directories of Windows OS.
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Let's sum it up
The phone writes that there is not enough memory, although it is there when you try to install an application - Android writes new programs to the internal memory, and a free flash drive does not help in this case. Universal ways to solve the problem are to clear temporary data and the cache of the Play Market and Google services, as well as remove unnecessary software. Some smartphones provide the ability to move programs from internal storage to a flash drive and erase Dalvik cache, which also helps solve the problem.
Volatile memory. RAM
What is volatile memory, and why is it called that?
Volatile memory is a type of memory that requires constant electrical power to store information.
This definition is quite rough, but perfectly reflects the principle of operation of the device.
During system operation, the necessary data is loaded into volatile memory. Information is stored and changed in the corresponding module exactly as long as power (electricity) is supplied to it. As soon as the power supply is stopped, all information from the volatile memory is lost. Actually, that’s why this type of memory is called volatile.
The best example, understandable to most readers, is Random Access Memory .
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Phone cleaning apps
Last, both in terms of importance and the extent to which I am willing to recommend it, are third-party applications for optimizing the operation of a smartphone. These include Clean Master, CCleaner, and even proprietary solutions from antivirus manufacturers - Avast and Kaspersky Lab.
All of these applications can really optimize the performance of a smartphone, but I still haven’t found one that suits me. In this regard, I trust the cleaning systems built into smartphones even more. I just don’t want to trust third-party applications with my smartphone and the data stored on it. Many will not agree with me, but I know for sure that many will support me.
Many cleaning applications use this symbol. It says a lot.
RAM
Many people are familiar with this concept, but for those who do not quite understand what will be discussed below, we will give a general definition of this term.
RAM is a volatile part of the device that stores code and data that requires instant access and is being processed in a given period of time.
RAM can often be referred to by the following abbreviations:
- RAM - Random Access Memory, which translated from English means “random access memory”;
- RAM – which stands for Random Access Memory.
During system operation, data and code that are currently being accessed by the processor are loaded into RAM. This information is stored and changed in the corresponding module exactly as long as power (electricity) is supplied to it. As soon as the power supply is stopped, all information from the RAM is lost.
In some systems, it is possible to implement data backup from RAM to a non-volatile memory module, but this issue is beyond the scope of this article and does not negate the differences in the functional features of these types of devices
find out the size of the device’s RAM and the amount of free memory not only using third-party programs that display such information, but also using standard means. For example, on some devices, the numbers you are looking for can be seen by opening the Applications menu in the phone settings and going to the Running tab
Here we see how much RAM is occupied by the system, currently running applications and how many Megabytes (in our case) are still free for use. Information about the total amount of available memory is also published in the technical information of the device.
In the Android , the size of RAM plays an important role. In addition to the fact that some programs themselves are quite demanding on the device’s hardware, the importance of the size and performance of the RAM partition is aggravated by the presence of multitasking in Android OS.
Multitasking is the ability of an operating system to perform two or more different tasks in parallel at one point in time.
The Android system independently manages the device's RAM. The RAM constantly keeps running the programs and services that the system and the user need at the moment. When launching new applications, software that has the lowest priority relative to other programs will be unloaded from RAM.
However, if the user is not satisfied with the way the system manages the available volume of the RAM , he can independently influence the list of programs in memory. can manage running applications and services, unload them, automatically terminate them, or completely prohibit them from starting using numerous Task killer and startup managers .
It is important to understand that in pursuit of a large amount of free RAM you should not act at the expense of the ease of use of the device
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How to clear memory. Various options
The most hardcore method is Hard Reset or Hard Reboot . In this way, we will return the phone to its original condition, as when purchased. It can be used by those who are too lazy to tinker with their phone and want to solve the problem of full memory in one fell swoop.
A more conservative way is to remove unnecessary applications and files, as well as cache and application updates . You can do this manually, or you can use special utilities, for example: Clean Master or CCleaner. After you use them, these utilities can be removed. FYI: The fewer apps you keep on your phone, the longer your battery lasts. Follow this advice: Keep at least 500 megabytes of free space. If you use Total Commander to delete files, then simply hold down the file, highlight it, and press the Delete button. If you use the ES Explorer utility, then you need to know that it has its own built-in recycle bin. You have cleared your phone of unnecessary files, please go to the trash and empty it, otherwise deleting will not add more space.
You can clean your phone using the All in one app. It has a Cleaning item, the phone is scanned, then a list of garbage is displayed that fits the “Can be deleted” category, these could be the remains of deleted applications. In the Advanced tab, you can clear your browser and mail history.
The cache is accumulated by applications, in which they store their data. The more apps you use, the more cache will accumulate on your phone. Clearing the cache is very simple: 2 options - using standard phone tools, installing special applications. The issue of installing applications is becoming moot, there is not enough space on the phone, so choose for yourself which method to use.
The standard method is the most obvious, go to the application manager, open any application, there is a cache clearing option. Android 6 has a Storage and USB drives item, where applications are very conveniently sorted by occupied space. You need to understand that if this is a game, for example, all your progress in the game will be reset. Or registration data in another application. If you start playing again, the cache will accumulate again.
also move already saved files from the internal memory to the memory card . To do this, check the following folders:
- Music - music
- Video
- DICM - photos and videos from the camera
- Bluetooth
- Download - everything you download from the Internet
- Media
- Movies
- Sounds
In addition to these folders, you need to find folders by application names, for example, you have Viber, look for a folder with the same name and move or delete files (videos, pictures, etc.). Delete or move only those files that you know, if you don't know what the file is for, then don't touch it, otherwise you will damage the application.
You can move files both on the phone itself and through a computer. Both methods are very easy, choose the one that is more convenient for you.
In order to transfer files via your computer, you will need a USB cable with which you will connect your phone to your PC. Also, don't forget to install the USB driver for your phone on your computer. Otherwise the computer will not see it.
If you want to use the built-in capabilities of your smartphone to move files from the phone’s internal memory to an SD card, then you will need any file manager, be it the built-in manager, or install any other one from the Play Store, it will be more convenient to use than the built-in one.
There is also a third way to move files; it combines the first and second methods. That is, you move without having to dig around inside the phone, and you don't need a USB cable. For this, there is a service called AirDroid, which can be downloaded from the Play Store. It allows you to connect your phone to your computer remotely, that is, wirelessly.
If you are wondering what other alternatives to a memory card are there for storing files and data, then you should find out more about the various cloud storage services, they are quite convenient as you will have access to them directly from your phone. The Google Photos app allows you to send your latest photos directly to the cloud. If you go to the application settings, you can click the Free up space button, and photos that are definitely already in the cloud will be deleted from your phone. The downside of cloud storage is that you need the Internet to view photos.
You can move apps from internal memory to SD card . Please note that not all applications can be moved, and also that the application is not completely moved to the memory card.
The most interesting way, from the point of view of effectiveness, is to combine the memory card with the internal memory of the smartphone, that is, the card and the phone become one. Some new models do this automatically; after inserting a memory card into the slot, a function is activated that asks the owner if he would like to combine two spaces into one. Well, you'll have to tinker with the rest of the phones, but you can combine them too.
Non-volatile memory. ROM
Non-volatile Random Access Memory is a type of memory device that does not require constant electrical power to store information.
This type of memory is used for various purposes: storing firmware (device operating system) files, storing recovery partitions, placing system partitions, recording and storing user data, and so on.
During the use of non-volatile memory by the system and the user, any information corresponding to the memory section is written to the device, which can be read from there if necessary. If the equipment is turned off and the power supply to the device is stopped, the information from it does not disappear; after restarting the system, all data will be available again. That is, this type of memory does not depend on the availability of power and is therefore called non-volatile.
Simple examples of non-volatile storage devices: hard disk drive (HDD), solid state drives (SSD), flash memory (SD).
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Flashable partition in Android. PROM
The abbreviation PROM stands for Programmable Read-Only Memory , which translated from English means “Programmable Read-Only Memory”, in more literate language - Programmable Read-Only Memory, abbreviated PROM . From this we can derive the definition:
Flashable PROM (Programmable Read-Only Memory) partition is a permanent memory sector that can only be changed using firmware
Let's look at the main sections of the Android operating system related to PROM , in the order in which they are accessed:
- Bootloader (HBOOT) - operating system bootloader. This is the memory sector that is the first to react when the device is turned on. It is interesting to the user because it analyzes whether additional buttons are pressed at the moment of turning on, and determines in which mode the device should be started. Used to flash smartphone firmware.
- Recovery is a section containing system software designed to diagnose the device, restore the system and create backup copies. Modern custom recovery ( custom recovery ) have wider functionality, allow you to install third-party firmware, have a built-in file manager, and so on.
- Boot is a memory section in the Android system that contains the OS kernel, drivers and files necessary to control the device at a low level (processor and memory commands). It is possible to overwrite this partition without replacing the main firmware.
- System - system partition containing firmware files, standard programs and operating system libraries. System section can be changed if the user has root . For example, by properly editing the hosts , located on the path /system/etc/hosts, you can get rid of advertising on your Android phone (more about this in the corresponding article: Removing advertising on Android. Hosts file )
All four Android memory sections described above are system and conditionally uneditable. Another feature of these partitions is connected with this: if you return to the standard settings of the device (full reset) from the device menu or Wipe data/factory reset from Recoery , then the above partitions are NOT formatted. If a failure occurs in one of these areas or some other problems arise, then to fix them it will be necessary to flash the device completely or the corresponding part of the memory.
Now let's look at that part of the memory that can be changed by the user independently and without root rights.
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Dalvik cache
Dalvik is a virtual machine that is used by Android devices to optimize applications. It also accumulates cache over time, stored in a hidden section of the smartphone’s memory. To remove Dalvik cache you need to follow these steps (not available on all Android gadgets):
- Turn off the phone and start it in Recovery Mode. To do this, you need to hold down the power button and volume control at the same time.
- In the Recovery menu, select “Wipe cache partition”. Control in this mode is carried out with the volume keys and the power button.
- Go to the “Advanced Options” section. Click “Wipe Dalvik Cache”.
- Restart your smartphone in normal mode.
Note: if you accidentally deleted an unread message, find out how to recover SMS on Android.
