fs: raise default max file descriptors from 16384 to 65536 - #1485
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The default fs_max_file_descriptors is 0x4000 (16384), which sizes the global file-descriptor table in fs/vfs/kern_descrip.cc. Server workloads that keep many files and sockets open concurrently (for example a database under high connection count, where each backend accumulates open relation files, WAL segments, and client sockets) can exhaust this table and hit EMFILE, at which point the affected component typically aborts rather than degrades. Raise the compile-time default to 0x10000 (65536). This is still a configurable Kconfig value, so images that want the smaller table can set it back. The table is an array of pointers, so the extra headroom costs a few hundred KB of kernel memory at most. Signed-off-by: Greg Burd <greg@burd.me>
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The default
fs_max_file_descriptorsis 0x4000 (16384), which sizes the global file-descriptor table infs/vfs/kern_descrip.cc. Server workloads that keep many files and sockets open concurrently can exhaust this table and hitEMFILE, at which point the affected component typically aborts rather than degrades.This was observed with a database under high connection count: each backend accumulates open relation files, WAL segments, and client sockets, and a busy sweep drives the live fd count past 16384, producing
EMFILEin the WAL writer and an abort.Raise the compile-time default to 0x10000 (65536). It remains a configurable Kconfig value, so images that want the smaller table can set it back. The table is an array of pointers, so the extra headroom costs a few hundred KB of kernel memory at most.
Standalone change, no dependencies.