redis resource_error ai_generated true

错误：BGSAVE 失败，因为 fork 失败：无法分配内存

Error: BGSAVE failed because fork failed: Cannot allocate memory

ID: redis/err-bgsave-failed-disk

其他格式: JSON · Markdown 中文 · English
80%修复率
90%置信度
1证据数
2023-11-20首次发现

版本兼容性

版本状态引入弃用备注
Redis 6.2.8 active — — —
Redis 7.0.13 active — — —
Linux kernel 5.10 active — — —
Linux kernel 6.1 active — — —

根因分析

Redis 服务器尝试 fork 子进程以执行 BGSAVE 失败，原因是系统内存不足，通常是由于内存过提交设置或高内存使用率。

English

The Redis server's attempt to fork a child process for BGSAVE failed due to insufficient system memory, often because of overcommit memory settings or high memory usage.

generic

官方文档

https://redis.io/docs/latest/operate/oss_and_stack/management/persistence/

解决方案

  1. Enable overcommit memory on the Linux host: `echo 1 > /proc/sys/vm/overcommit_memory` and make it persistent in /etc/sysctl.conf with `vm.overcommit_memory = 1`.
  2. Reduce Redis memory usage by setting a lower `maxmemory` value or evicting keys with `maxmemory-policy allkeys-lru`. Restart Redis after changes.
  3. Use a smaller fork-friendly configuration: set `repl-diskless-sync yes` to avoid fork during replication, or switch to AOF with `appendonly yes` and `no-appendfsync-on-rewrite yes`.

无效尝试

常见但无效的做法:

  1. 95% 失败

    The fork failure is at the OS level, not Redis config.

  2. 70% 失败

    Swap can provide a buffer; disabling it may cause immediate OOM kills.