Dengan mengonfigurasi parameter kernel, AlloyDB Omni dapat menggunakan memori sistem dan resource IO secara lebih efisien saat menangani workload berat.
Prasyarat
Sebelum memulai, pastikan node Kubernetes Anda menjalankan kernel Linux 6.1 atau yang lebih baru, khususnya kernel yang mendukung flag MADV_COLLAPSE dan MADV_POPULATE_WRITE. Untuk mengetahui informasi selengkapnya tentang flag ini, lihat dokumentasi madwise Linux.
Menerapkan setelan kernel yang direkomendasikan ke node Kubernetes
Tabel berikut mencantumkan parameter kernel yang diperlukan dan nilai yang sesuai untuk node Kubernetes yang menjalankan pod cluster database:
File
Nilai
/sys/kernel/mm/transparent_hugepage/shmem_enabled Untuk mengetahui informasi tentang memori bersama, lihat Dukungan Hugepage Transparan
within_size atau always
/proc/sys/vm/max_map_count Untuk mengetahui informasi tentang jumlah area peta memori yang dapat dibuat oleh suatu proses, lihat Dokumentasi untuk /proc/sys/vm
Lebih besar dari atau sama dengan 1073741824
Untuk mengonfigurasi parameter kernel di node Kubernetes menggunakan DaemonSet, lakukan hal berikut:
Terapkan label ke node tempat Anda berencana menjalankan cluster database menggunakan petunjuk di Menambahkan label ke node.
Untuk menyetel parameter kernel pada node yang diberi label LABEL_KEY=LABEL_VALUE, buat DaemonSet:
DS_NAMESPACE: namespace tempat Anda ingin men-deploy DaemonSet—misalnya, default.
LABEL_KEY: ID untuk label—misalnya, workload.
LABEL_VALUE: data yang terkait dengan ID untuk label—misalnya, database.
INIT_IMAGE: nama image yang digunakan untuk init container.
MAX_MAP_COUNT: jumlah maksimum area peta memori yang dapat dibuat oleh suatu proses—misalnya, 1073741824.
CONTAINER_NAME: nama penampung utama—misalnya, main.
CONTAINER_IMAGE: nama image yang digunakan untuk container utama—misalnya, latest.
Setelah men-deploy DaemonSet, untuk memverifikasi bahwa semua pod di cluster Kubernetes Anda berada dalam status Running dan Anda memiliki satu pod untuk setiap node dengan label LABEL_KEY=LABEL_VALUE, gunakan perintah berikut:
kubectlgetpods-lLABEL_KEY=LABEL_VALUE
Contoh outputnya akan terlihat seperti berikut:
NAME READY STATUS RESTARTS AGE
alloydb-omni-kernel-tuning-2dkwh 1/1 Running 0 22s
alloydb-omni-kernel-tuning-pgkbj 1/1 Running 0 19s
Untuk memverifikasi bahwa tanda kernel berhasil diterapkan, untuk setiap pod yang diidentifikasi setelah men-deploy DaemonSet, jalankan perintah berikut:
kubectllogsPOD_NAME
Ganti POD_NAME dengan nama pod yang lognya ingin Anda periksa.
Contoh outputnya akan terlihat seperti berikut:
always [within_size] advise never deny force
Menjalankan cluster database di node Kubernetes dengan parameter kernel yang direkomendasikan
Untuk men-deploy cluster database di node Kubernetes dengan parameter kernel yang direkomendasikan, tambahkan bagian nodeAffinity ke salah satu bagian berikut dari manifes cluster database Anda:
primarySpec.schedulingConfig untuk instance utama
spec.schedulingConfig untuk instance kumpulan baca
Untuk memverifikasi bahwa parameter kernel diterapkan ke pod database, lakukan hal berikut:
Jika ketersediaan tinggi diaktifkan, khususnya spec.availability.numberOfStandbys disetel ke nilai yang lebih besar dari nol, verifikasi bahwa resource kustom database menampilkan DBClusterReady di kolom DBCLUSTERPHASE dan True di kolom HAREADYSTATUS.
[[["Mudah dipahami","easyToUnderstand","thumb-up"],["Memecahkan masalah saya","solvedMyProblem","thumb-up"],["Lainnya","otherUp","thumb-up"]],[["Sulit dipahami","hardToUnderstand","thumb-down"],["Informasi atau kode contoh salah","incorrectInformationOrSampleCode","thumb-down"],["Informasi/contoh yang saya butuhkan tidak ada","missingTheInformationSamplesINeed","thumb-down"],["Masalah terjemahan","translationIssue","thumb-down"],["Lainnya","otherDown","thumb-down"]],["Terakhir diperbarui pada 2025-09-04 UTC."],[],[],null,["# Configure kernel parameters for AlloyDB Omni on Kubernetes\n\nSelect a documentation version: 16.8.0keyboard_arrow_down\n\n- [Current (16.8.0)](/alloydb/omni/current/docs/optimize-database-performance-configure-kernel-kubernetes)\n- [16.8.0](/alloydb/omni/16.8.0/docs/optimize-database-performance-configure-kernel-kubernetes)\n- [16.3.0](/alloydb/omni/16.3.0/docs/optimize-database-performance-configure-kernel-kubernetes)\n- [15.12.0](/alloydb/omni/15.12.0/docs/optimize-database-performance-configure-kernel-kubernetes)\n- [15.7.1](/alloydb/omni/15.7.1/docs/optimize-database-performance-configure-kernel-kubernetes)\n- [15.7.0](/alloydb/omni/15.7.0/docs/optimize-database-performance-configure-kernel-kubernetes)\n\n\u003cbr /\u003e\n\nThis page provides information about setting up Kubernetes nodes that host AlloyDB Omni database clusters for the optimal performance of the AlloyDB Omni Kubernetes operator and the AlloyDB Omni database engine.\n\n\u003cbr /\u003e\n\nConfiguring kernel parameters lets AlloyDB Omni use system memory and IO resources more efficiently when handling heavy workloads.\n\nPrerequisite\n------------\n\nBefore you start, make sure your Kubernetes nodes run Linux kernel 6.1 or higher, specifically a kernel that supports the `MADV_COLLAPSE` and `MADV_POPULATE_WRITE` flags. For more information about these flags, see [Linux `madwise` documentation](https://man7.org/linux/man-pages/man2/madvise.2.html).\n\nApply recommended kernel settings to Kubernetes nodes\n-----------------------------------------------------\n\nThe following table lists required kernel parameters and their corresponding values for Kubernetes nodes that run database cluster pods:\n\nTo configure the kernel parameters on your Kubernetes nodes using a [DaemonSet](https://kubernetes.io/docs/concepts/workloads/controllers/daemonset/), do the following:\n\n1. Apply labels to the nodes where you plan to run database clusters using instructions in [Add a label to a node](https://kubernetes.io/docs/tasks/configure-pod-container/assign-pods-nodes/#add-a-label-to-a-node).\n\n2. To set the kernel parameters on the nodes labeled `LABEL_KEY=LABEL_VALUE`, create a DaemonSet:\n\n cat \u003c\u003c EOF | kubectl apply -f -\n apiVersion: apps/v1\n kind: DaemonSet\n metadata:\n name: alloydb-omni-kernel-tuning\n namespace: \u003cvar translate=\"no\"\u003e\u003cspan class=\"devsite-syntax-l devsite-syntax-l-Scalar devsite-syntax-l-Scalar-Plain\"\u003eDS_NAMESPACE\u003c/span\u003e\u003c/var\u003e\n spec:\n selector:\n matchLabels:\n name: alloydb-omni-kernel-tuning\n template:\n metadata:\n labels:\n name: alloydb-omni-kernel-tuning\n spec:\n volumes:\n - name: host-sys\n hostPath:\n path: /sys\n nodeSelector:\n \u003cvar translate=\"no\"\u003e\u003cspan class=\"devsite-syntax-nt\"\u003eLABEL_KEY\u003c/span\u003e\u003c/var\u003e: \"\u003cvar translate=\"no\"\u003eLABEL_VALUE\u003c/var\u003e\"\n restartPolicy: Always\n terminationGracePeriodSeconds: 1\n initContainers:\n - name: enable-thp-mmc\n image: \u003cvar translate=\"no\"\u003e\u003cspan class=\"devsite-syntax-l devsite-syntax-l-Scalar devsite-syntax-l-Scalar-Plain\"\u003eINIT_IMAGE\u003c/span\u003e\u003c/var\u003e\n volumeMounts:\n - name: host-sys\n mountPath: /sys\n securityContext:\n privileged: true\n command: [\"sh\", \"-c\", \"sysctl -w vm.max_map_count=\u003cvar translate=\"no\"\u003eMAX_MAP_COUNT\u003c/var\u003e && echo within_size \u003e/sys/kernel/mm/transparent_hugepage/shmem_enabled\"]\n containers:\n - name: \u003cvar translate=\"no\"\u003e\u003cspan class=\"devsite-syntax-l devsite-syntax-l-Scalar devsite-syntax-l-Scalar-Plain\"\u003eCONTAINER_NAME\u003c/span\u003e\u003c/var\u003e\n image: \u003cvar translate=\"no\"\u003e\u003cspan class=\"devsite-syntax-l devsite-syntax-l-Scalar devsite-syntax-l-Scalar-Plain\"\u003eCONTAINER_IMAGE\u003c/span\u003e\u003c/var\u003e\n command: [\"watch\", \"-n\", \"600\", \"cat\", \"/sys/kernel/mm/transparent_hugepage/shmem_enabled\"]\n EOF\n\n Replace the following:\n - \u003cvar translate=\"no\"\u003eDS_NAMESPACE\u003c/var\u003e: the namespace where you want to deploy the DaemonSet---for example, `default`.\n - \u003cvar translate=\"no\"\u003eLABEL_KEY\u003c/var\u003e: the identifier for the label---for example, `workload`.\n - \u003cvar translate=\"no\"\u003eLABEL_VALUE\u003c/var\u003e: the data associated with the identifier for the label---for example, `database`.\n - \u003cvar translate=\"no\"\u003eINIT_IMAGE\u003c/var\u003e: the name of the image used for the init container.\n - \u003cvar translate=\"no\"\u003eMAX_MAP_COUNT\u003c/var\u003e: the maximum number of memory map areas a process can create---for example, `1073741824`.\n - \u003cvar translate=\"no\"\u003eCONTAINER_NAME\u003c/var\u003e: the name of the main container---for example, `main`.\n - \u003cvar translate=\"no\"\u003eCONTAINER_IMAGE\u003c/var\u003e: the name of the image used for the main container---for example, `latest`.\n3. After deploying the DaemonSet, to verify that all pods in your Kubernetes cluster are in the `Running` state and that you have one pod for each node with the label \u003cvar translate=\"no\"\u003eLABEL_KEY\u003c/var\u003e`=`\u003cvar translate=\"no\"\u003eLABEL_VALUE\u003c/var\u003e, use the following command:\n\n kubectl get pods -l \u003cvar translate=\"no\"\u003e\u003cspan class=\"devsite-syntax-nv\"\u003eLABEL_KEY\u003c/span\u003e\u003c/var\u003e=\u003cvar translate=\"no\"\u003eLABEL_VALUE\u003c/var\u003e\n\n An example output looks as follows: \n\n NAME READY STATUS RESTARTS AGE\n alloydb-omni-kernel-tuning-2dkwh 1/1 Running 0 22s\n alloydb-omni-kernel-tuning-pgkbj 1/1 Running 0 19s\n\n4. To verify the kernel flag is successfully applied, for each of the pods identified after deploying the DaemonSet, run the following command:\n\n kubectl logs \u003cvar translate=\"no\"\u003ePOD_NAME\u003c/var\u003e\n\n Replace \u003cvar translate=\"no\"\u003ePOD_NAME\u003c/var\u003e with the name of the pod you want to examine the logs of.\n\n An example output looks as follows: \n\n always [within_size] advise never deny force\n\nRun database clusters on Kubernetes nodes with recommended kernel parameters\n----------------------------------------------------------------------------\n\nTo deploy database clusters on Kubernetes nodes with recommended kernel parameters, add a `nodeAffinity` section to one of the following sections of your database cluster manifest:\n\n- `primarySpec.schedulingConfig` for primary instances\n- `spec.schedulingConfig` for read pool instances\n\n nodeaffinity:\n requiredDuringSchedulingIgnoredDuringExecution:\n nodeSelectorTerms:\n - matchExpressions:\n - key: \u003cvar translate=\"no\"\u003e\u003cspan class=\"devsite-syntax-l devsite-syntax-l-Scalar devsite-syntax-l-Scalar-Plain\"\u003eLABEL_KEY\u003c/span\u003e\u003c/var\u003e\n operator: In\n values:\n - \"\u003cvar translate=\"no\"\u003eLABEL_VALUE\u003c/var\u003e\"\n\nFor more information about running database clusters on specific Kubernetes nodes, see [Assign nodes to a database cluster using scheduling](/alloydb/omni/16.8.0/docs/assign-nodes-cluster-scheduling).\n\n### Verify the application of kernel parameters\n\nTo verify kernel parameters are applied to database pods, do the following:\n\n1. If high availability is enabled, specifically `spec.availability.numberOfStandbys` is set to a value greater than zero, verify that the database custom resource shows `DBClusterReady` in the **DBCLUSTERPHASE** column and `True` in the **HAREADYSTATUS** column.\n\n kubectl get dbcluster -n \u003cvar translate=\"no\"\u003eDBCLUSTER_NAMESPACE\u003c/var\u003e \u003cvar translate=\"no\"\u003eDBCLUSTER_NAME\u003c/var\u003e\n\n Replace the following:\n - \u003cvar translate=\"no\"\u003eDBCLUSTER_NAME\u003c/var\u003e: the name of the database cluster you verify.\n - \u003cvar translate=\"no\"\u003eDBCLUSTER_NAMESPACE\u003c/var\u003e: the name of the specific namespace where your database cluster resides.\n\n An example output looks as follows: \n\n NAME PRIMARYENDPOINT PRIMARYPHASE DBCLUSTERPHASE HAREADYSTATUS HAREADYREASON\n dbcluster-sample 10.29.21.240 Ready DBClusterReady True Ready\n\n2. List Kubernetes pods that belong to the database cluster:\n\n kubectl get pods -n \u003cvar translate=\"no\"\u003eDBCLUSTER_NAMESPACE\u003c/var\u003e -l alloydbomni.internal.dbadmin.goog/dbcluster=\u003cvar translate=\"no\"\u003eDBCLUSTER_NAME\u003c/var\u003e\n\n3. To check shared memory information, run the following command:\n\n kubectl exec -n \u003cvar translate=\"no\"\u003eDBCLUSTER_NAMESPACE\u003c/var\u003e \u003cvar translate=\"no\"\u003ePOD_NAME\u003c/var\u003e -- grep Shmem /proc/meminfo\n\n4. The output must contain numbers other than zero in all of the entries.\n\n An example output looks as follows: \n\n Shmem: 126255872 kB\n ShmemHugePages: 18403328 kB\n ShmemPmdMapped: 2961408 kB\n\n If you see `0 kB` shows in any of the entries, restart the corresponding pod: \n\n kubectl delete pod -n \u003cvar translate=\"no\"\u003eDBCLUSTER_NAMESPACE\u003c/var\u003e \u003cvar translate=\"no\"\u003ePOD_NAME\u003c/var\u003e\n\n5. Repeat steps 1 through 5 after the pod is in the `Running` state."]]
