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64K should enable support for <= 64K. Default was system page size which means binaries only run on 4K. See:

• uv: set JEMALLOC_SYS_WITH_LG_PAGE for ARM64 Linux builds homebrew-core#234353
• fd: set JEMALLOC_SYS_WITH_LG_PAGE for ARM64 linux builds homebrew-core#234516

Can see other usage in:

• Rust: https://github.com/rust-lang/rust/blob/master/src/bootstrap/src/core/build_steps/tool.rs#L231-L237

      // Build jemalloc on AArch64 with support for page sizes up to 64K
      // See: https://github.com/rust-lang/rust/pull/135081
      // Note that `miri` always uses jemalloc. As such, there is no checking of the jemalloc build flag.
      // See also the "JEMALLOC_SYS_WITH_LG_PAGE" setting in the compile build step.
      if target.starts_with("aarch64") && env::var_os("JEMALLOC_SYS_WITH_LG_PAGE").is_none() {
          cargo.env("JEMALLOC_SYS_WITH_LG_PAGE", "16");
      }

• fd: https://github.com/sharkdp/fd/blob/master/Cross.toml#L2-L3

  [target.aarch64-unknown-linux-gnu.env]
  passthrough = ["JEMALLOC_SYS_WITH_LG_PAGE=16"]

• Guix (only 16K): https://codeberg.org/guix/guix/src/branch/master/guix/build/cargo-build-system.scm#L216-L218

  ;; Support 16k kernel page sizes on aarch64 with jemalloc.
  --
  (when (string-prefix? "aarch64" (or target system))
  (setenv "JEMALLOC_SYS_WITH_LG_PAGE" "14"))