diff --git a/.cargo/config.toml b/.cargo/config.toml
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+[env]
+# environment variable for tikv-jemalloc-sys
+#
+# https://jemalloc.net/jemalloc.3.html#opt.narenas
+# narenas is the maximum number of arenas to use for automatic multiplexing
+# of threads and arenas. The default is four times the number of CPUs,
+# or one if there is a single CPU.
+#
+# Improve memory efficiency by reducing fragmentation and ensuring all threads allocate from the same pool
+JEMALLOC_SYS_WITH_MALLOC_CONF = "narenas:1"