Akka threads constant in futex_ state -- Is this normal?

I have an Akka program with threads that are spending most of their time in the futex_ state.

This is from an Akka program that isn't doing much. I am not familiar with the internals of Akka, so I'm not sure if this is normal or not.

F S   UID    PID   PPID    LWP  C PRI  NI ADDR SZ WCHAN  TTY        TIME CMD
4 S     1     19      0     19  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
5 S     1     19      0     25  0  80   0 - 1149556 futex_ ?        0:04 /usr/bin/java
1 S     1     19      0     26  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0     27  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0     28  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0     29  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0     30  1  80   0 - 1149556 futex_ ?        0:12 /usr/bin/java
1 S     1     19      0     31  0  80   0 - 1149556 futex_ ?        0:04 /usr/bin/java
1 S     1     19      0     32  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0     33  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0     43  0  80   0 - 1149556 futex_ ?        0:02 /usr/bin/java
1 S     1     19      0     44  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0     45  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0     46  0  80   0 - 1149556 futex_ ?        0:01 /usr/bin/java
1 S     1     19      0     47  0  80   0 - 1149556 futex_ ?        0:02 /usr/bin/java
1 S     1     19      0     50  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0     53  0  80   0 - 1149556 futex_ ?        0:01 /usr/bin/java
1 S     1     19      0     60  0  80   0 - 1149556 futex_ ?        0:03 /usr/bin/java
1 S     1     19      0    121  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0    122  0  80   0 - 1149556 futex_ ?        0:01 /usr/bin/java
1 S     1     19      0    123  0  80   0 - 1149556 ep_pol ?        0:00 /usr/bin/java
1 S     1     19      0    282  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0    283  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0    284  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0    285  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0    295  0  80   0 - 1149556 futex_ ?        0:01 /usr/bin/java
1 S     1     19      0    383  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java
1 S     1     19      0    433  0  80   0 - 1149556 futex_ ?        0:01 /usr/bin/java
1 S     1     19      0   1109  0  80   0 - 1149556 futex_ ?        0:00 /usr/bin/java

Checking the syscalls, there are a ton of timed out futex calls constantly happening. Here's a snippet from just a fraction of a second:

[pid    43] futex(0x7f36266dfc28, FUTEX_WAKE_PRIVATE, 1) = 0
[pid    43] futex(0x7f36266dfc54, FUTEX_WAIT_BITSET_PRIVATE, 1, {tv_sec=14532, tv_nsec=950443844}, 0xffffffff <unfinished ...>
[pid    47] <... futex resumed> )       = -1 ETIMEDOUT (Connection timed out)
[pid    47] futex(0x7f3626f8ab28, FUTEX_WAKE_PRIVATE, 1) = 0
[pid    47] futex(0x7f3626f8ab54, FUTEX_WAIT_BITSET_PRIVATE, 1, {tv_sec=14532, tv_nsec=954449564}, 0xffffffff <unfinished ...>
[pid    33] <... futex resumed> )       = -1 ETIMEDOUT (Connection timed out)
[pid    33] futex(0x7f3624a11128, FUTEX_WAKE_PRIVATE, 1) = 0
[pid    33] futex(0x7f3624a11154, FUTEX_WAIT_BITSET_PRIVATE, 1, {tv_sec=14532, tv_nsec=998037087}, 0xffffffff <unfinished ...>
[pid    43] <... futex resumed> )       = -1 ETIMEDOUT (Connection timed out)
[pid    43] futex(0x7f36266dfc28, FUTEX_WAKE_PRIVATE, 1) = 0
[pid    43] futex(0x7f36266dfc54, FUTEX_WAIT_BITSET_PRIVATE, 1, {tv_sec=14532, tv_nsec=960733704}, 0xffffffff <unfinished ...>
[pid    47] <... futex resumed> )       = -1 ETIMEDOUT (Connection timed out)
[pid    47] futex(0x7f3626f8ab28, FUTEX_WAKE_PRIVATE, 1) = 0
[pid    47] futex(0x7f3626f8ab54, FUTEX_WAIT_BITSET_PRIVATE, 1, {tv_sec=14532, tv_nsec=964665830}, 0xffffffff <unfinished ...>
[pid    43] <... futex resumed> )       = -1 ETIMEDOUT (Connection timed out)
[pid    43] futex(0x7f36266dfc28, FUTEX_WAKE_PRIVATE, 1) = 0
[pid    43] futex(0x7f36266dfc54, FUTEX_WAIT_BITSET_PRIVATE, 1, {tv_sec=14532, tv_nsec=971001771}, 0xffffffff <unfinished ...>
[pid    47] <... futex resumed> )       = -1 ETIMEDOUT (Connection timed out)
[pid    47] futex(0x7f3626f8ab28, FUTEX_WAKE_PRIVATE, 1) = 0
[pid    47] futex(0x7f3626f8ab54, FUTEX_WAIT_BITSET_PRIVATE, 1, {tv_sec=14532, tv_nsec=973981797}, 0xffffffff <unfinished ...>
[pid    43] <... futex resumed> )       = -1 ETIMEDOUT (Connection timed out)
[pid    43] futex(0x7f36266dfc28, FUTEX_WAKE_PRIVATE, 1) = 0
[pid    43] futex(0x7f36266dfc54, FUTEX_WAIT_BITSET_PRIVATE, 1, {tv_sec=14532, tv_nsec=980553240}, 0xffffffff <unfinished ...>
[pid    47] <... futex resumed> )       = -1 ETIMEDOUT (Connection timed out)

My theory is that this may be the Akka actors rapidly checking to see if there's any new work for them to do, but I am seeking confirmation if that is a valid theory. Thank you!