[[["เข้าใจง่าย","easyToUnderstand","thumb-up"],["แก้ปัญหาของฉันได้","solvedMyProblem","thumb-up"],["อื่นๆ","otherUp","thumb-up"]],[["ไม่มีข้อมูลที่ฉันต้องการ","missingTheInformationINeed","thumb-down"],["ซับซ้อนเกินไป/มีหลายขั้นตอนมากเกินไป","tooComplicatedTooManySteps","thumb-down"],["ล้าสมัย","outOfDate","thumb-down"],["ปัญหาเกี่ยวกับการแปล","translationIssue","thumb-down"],["ตัวอย่าง/ปัญหาเกี่ยวกับโค้ด","samplesCodeIssue","thumb-down"],["อื่นๆ","otherDown","thumb-down"]],["อัปเดตล่าสุด 2025-07-27 UTC"],[],[],null,["# Partitions overview\n\nAndroid devices contain several *partitions* or specific sections of storage\nspace used to contain specific parts of the device's software. Each partition\ncontains a *partition image* (an IMG file) or snapshot of all the software for\nthe partition. Figure 1 shows the layout of core partitions on a device:\n\n**Figure 1.** Layout of core partitions.\n\nPartitions are classified in three categories:\n\n- *System partitions* are partitions that are updated when updating the OS\n and other features. The `system`, `boot`, and `init_boot` are core system\n partitions.\n\n- *Vendor partitions* contain device and hardware-specific code that might\n never be updated after initial release. The `vendor`, `vendor_boot`, and `odm`\n partitions are core vendor partitions.\n\n- *Nonupdatable partitions* are partitions whose contents are either not updated\n or updated with user data.\n\nCode in system and vendor partitions can interact using a stable interface\ncalled the *vendor interface (VINTF)*.\n| **Note:** The separation of system partitions from vendor partitions was part of an Android 11 effort called *Project Treble*. With this architecture, you can update a device's operating system and apps without updating any of hardware-specific code.\n\n### System partitions\n\nFollowing is a list of all system partitions and their use:\n\n- **`boot` partition.** This partition contains a Generic Kernel Image (GKI).\n This partition also contains the generic ramdisk in devices launched in\n Android 12 and lower. For further information on generic ramdisk, see\n [Generic ramdisk image contents](/docs/core/architecture/partitions/generic-boot#generic-boot-ramdisk-image-contents).\n\n- **`init_boot` partition (Android 13 and higher).** This partition contains a\n generic ramdisk. In Android 11 and 12, the generic ramdisk is in the\n `boot` partition.\n\n- **`system` partition.** This partition contains the system image used\n for OEM products.\n\n- **`system_ext` partition.** This partition contains system resources and\n proprietary system modules that extend the common system image in the `system`\n partition.\n\n | **Note:** *Single system image (SSI)* refers to a file, such as a zip file that contains the images of the `system` and `system_ext` partitions and reuses those images across a set of target devices. For further information on SSI, see [Android shared system image](/docs/core/architecture/partitions/shared-system-image).\n- **`system_dlkm` partition.** This partition contains GKI modules. For further\n information on this partition, see [Implement a GKI module partition](/docs/core/architecture/partitions/gki-partitions).\n\n- **`product` partition.** This partition can contain product-specific modules\n that aren't bundled with any other partitions.\n\n | **Note:** The [*Vendor Native Development Kit (VNDK)*](/docs/core/architecture/vndk) is a set of libraries installed in the `system` partition and designed exclusively for vendors to implement their HALs. The `product` and `vendor` partitions can link to VNDK libraries in the `system` partition, but can't link to other libraries in the `system` partition.\n- **`pvmfw` partition.** This partition stores the Protected Virtual Machine\n Firmware (pvmfw) which is the first code that runs in protected VMs. For more\n information, see [Protected Virtual Machine Firmware](https://android.googlesource.com/platform/packages/modules/Virtualization/+/refs/heads/android16-release/guest/pvmfw/README.md).\n\n- **`generic_bootloader` partition.** This partition contains the generic bootloader.\n\n### Vendor partitions\n\nFollowing is a list of all vendor partitions and their use:\n\n- **`vendor_boot` partition.** This partition contains vendor-specific boot\n code. For more information, see [Vendor boot partitions](/docs/core/architecture/partitions/vendor-boot-partitions).\n\n- **`recovery` partition.** This partition stores the recovery image, which is\n booted during the over-the-air (OTA) update process. Devices that support\n seamless updates can store the recovery images as a ramdisk contained in the\n `boot` or `init_boot` image. For more information on seamless updates,\n see [A/B (seamless) updates](/docs/core/ota/ab).\n\n- **`misc` partition.** This partition is used by the recovery partition and is\n 4 KB or larger.\n\n- **`vbmeta` partition.** This partition contains the Verified Boot information\n for all of the partitions. This information verifies that the images installed\n in each partition is trusted. For further information on\n Verified Boot, see\n [Verified Boot](/docs/security/features/verifiedboot).\n\n- **`vendor` partition.** This partition contains any binary that is vendor\n specific and not generic enough to distribute to AOSP.\n\n | **Note:** The [*Vendor Native Development Kit (VNDK)*](/docs/core/architecture/vndk) is a set of libraries installed in the `system` partition and designed exclusively for vendors to implement their HALs. The `product` and `vendor` partitions can link to VNDK libraries in the `system` partition, but can't link to other libraries in the `system` partition.\n- **`vendor_dlkm` partition.** This partition contains vendor\n kernel modules. By storing vendor kernel modules in this partition\n instead of the `vendor` partition, you can update kernel\n modules without updating the `vendor` partition. For more information, see\n [Vendor and ODM DKLM partitions](/docs/core/architecture/partitions/vendor-odm-dlkm-partition).\n\n- **`odm` partition.** This partition contains original design manufacturer\n (ODM)\n customizations to system-on-chip (SoC) vendor board-support packages (BSPs).\n Such customizations enable ODMs to replace or customize SoC components, and\n implement kernel modules for board-specific components, daemons, and\n ODM-specific features on hardware abstraction layers (HALs). This partition is\n optional. Typically this partition is used to contain customizations so that\n devices can\n use a single vendor image for multiple hardware SKUs. For more information,\n see [ODM partitions](/docs/core/architecture/bootloader/partitions/odm-partitions).\n\n- **`odm_dlkm` partition.** This partition is dedicated to storing ODM kernel\n modules. By storing ODM kernel modules in the this partition, instead of\n the `odm` partition, you can update ODM kernel modules without updating the\n `odm` partition. For more information, see\n [Vendor and ODM DKLM partitions](/docs/core/architecture/partitions/vendor-odm-dlkm-partition).\n\n- **`radio` partition.** This partition contains the radio image and is needed\n only for devices that include a radio with radio-specific software in a\n dedicated partition.\n\n| **Note:** Devices that support seamless updates need two partitions, referred to as *slots* (slot A and slot B) for the `boot`, `system`, `vendor`, and `radio` partitions. For further information, see [Partition selection (slots)](/docs/core/ota/ab#slots).\n\n### Nonupdatable partitions\n\nFollowing is a list of all nonupdatable partitions and their use:\n\n- **`cache` partition.** This partition contains temporary data and is optional\n if your device uses seamless updates. This partition doesn't need to be\n writable from the bootloader, but needs to be erasable. The partition\n size depends on the device type and the availability of space on `userdata`;\n typically, 50 to 100 MB is sufficient.\n\n- **`userdata` partition.** This partition contains user-installed apps and\n data, including customization data.\n\n- **`metadata` partition.** If your device uses [metadata encryption](/docs/security/features/encryption/metadata),\n this partition contains the metadata encryption key. The size of this\n partition is 16 MB or larger, it isn't encrypted, and its data isn't\n snapshotted. This partition is erased when the device is factory reset.\n\nPartition update rules and recommendations\n------------------------------------------\n\nWe recommend updating all system partitions as a whole\nand all vendor partitions as another whole. By updating the set of partitions as\na whole, you can test to verify the interfaces between images in each partition\nremain stable.\n\nRegardless of how you update your partitions, the following partitions must\nbe updated due to tightly coupled dependencies and lack of stable APIs:\n\n- The `boot` and `system_dlkm` partitions\n- the `init_boot`, `system`, `system_ext`, and `product` partitions\n\n| **Note:** If all interfaces between the `product` partition and other system partitions have stable ABIs, you can update the `product` partition independently. For furthe information, see [Maintain ABIs between partitions](/docs/core/architecture/partitions/product-partitions#maintaining-abis).\n\nDynamic partitions\n------------------\n\nDevices running Android 11 and higher can support\ndynamic partitions, which are a userspace partitioning system for Android that\nlets you create, resize, or destroy partitions during over-the-air (OTA)\nupdates. For more information, see [Dynamic partitions](/docs/core/ota/dynamic_partitions).\n\n### Soong product variants\n\nThe [Soong](/docs/setup/build) build system uses image variants to split\nbuild dependencies. Native modules (`/build/soong/cc`) can mutate system\nprocess modules to the core variant and vendor process modules to the\nvendor variant; a module in one image variant can't link to other modules in\na different image variant.\n\nIn Android 12 or higher, a system module with\n`vendor_available: true` creates a vendor variant in addition to the core\nvariant. To create a product variant, `product_available: true` must be\ndefined. Some VNDK libraries without `product_available: true` aren't\navailable to product modules."]]
