diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index 97c05e18f9..8073925b4a 100644
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -1594,7 +1594,12 @@ int cg_set_attribute(const char *controller, const char *path, const char *attri
         if (r < 0)
                 return r;
 
-        return write_string_file(p, value, WRITE_STRING_FILE_DISABLE_BUFFER);
+        /* https://lore.kernel.org/all/20250419183545.1982187-1-shakeel.butt@linux.dev/ adds O_NONBLOCK
+         * semantics to memory.max and memory.high to skip synchronous memory reclaim when O_NONBLOCK is
+         * enabled. Let's always open cgroupv2 attribute files in nonblocking mode to immediately take
+         * advantage of this and any other asynchronous resource reclaim that's added to the cgroupv2 API in
+         * the future. */
+        return write_string_file(p, value, WRITE_STRING_FILE_DISABLE_BUFFER|WRITE_STRING_FILE_OPEN_NONBLOCKING);
 }
 
 int cg_get_attribute(const char *controller, const char *path, const char *attribute, char **ret) {
diff --git a/src/basic/fileio.c b/src/basic/fileio.c
index eaadfaa6ac..97f92213da 100644
--- a/src/basic/fileio.c
+++ b/src/basic/fileio.c
@@ -317,7 +317,8 @@ int write_string_file_full(
                 r = fd = fd_reopen(
                                 ASSERT_FD(dir_fd), O_CLOEXEC | O_NOCTTY |
                                 (FLAGS_SET(flags, WRITE_STRING_FILE_TRUNCATE) ? O_TRUNC : 0) |
-                                (FLAGS_SET(flags, WRITE_STRING_FILE_SUPPRESS_REDUNDANT_VIRTUAL) ? O_RDWR : O_WRONLY));
+                                (FLAGS_SET(flags, WRITE_STRING_FILE_SUPPRESS_REDUNDANT_VIRTUAL) ? O_RDWR : O_WRONLY) |
+                                (FLAGS_SET(flags, WRITE_STRING_FILE_OPEN_NONBLOCKING) ? O_NONBLOCK : 0));
         else {
                 mode_t mode = write_string_file_flags_to_mode(flags);
                 bool call_label_ops_post = false;
@@ -335,7 +336,8 @@ int write_string_file_full(
                                 (FLAGS_SET(flags, WRITE_STRING_FILE_NOFOLLOW) ? O_NOFOLLOW : 0) |
                                 (FLAGS_SET(flags, WRITE_STRING_FILE_CREATE) ? O_CREAT : 0) |
                                 (FLAGS_SET(flags, WRITE_STRING_FILE_TRUNCATE) ? O_TRUNC : 0) |
-                                (FLAGS_SET(flags, WRITE_STRING_FILE_SUPPRESS_REDUNDANT_VIRTUAL) ? O_RDWR : O_WRONLY),
+                                (FLAGS_SET(flags, WRITE_STRING_FILE_SUPPRESS_REDUNDANT_VIRTUAL) ? O_RDWR : O_WRONLY) |
+                                (FLAGS_SET(flags, WRITE_STRING_FILE_OPEN_NONBLOCKING) ? O_NONBLOCK : 0),
                                 mode,
                                 &made_file);
                 if (call_label_ops_post)
diff --git a/src/basic/fileio.h b/src/basic/fileio.h
index b6513fe3f8..0297cd07e9 100644
--- a/src/basic/fileio.h
+++ b/src/basic/fileio.h
@@ -20,6 +20,7 @@ typedef enum {
         WRITE_STRING_FILE_MODE_0444                  = 1 << 11,
         WRITE_STRING_FILE_SUPPRESS_REDUNDANT_VIRTUAL = 1 << 12,
         WRITE_STRING_FILE_LABEL                      = 1 << 13,
+        WRITE_STRING_FILE_OPEN_NONBLOCKING           = 1 << 14,
 } WriteStringFileFlags;
 
 typedef enum {