diff --git a/.gitignore b/.gitignore
index ea8c4bf..8e0af9a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
-/target
+/target
+/keys.log
diff --git a/src/main.rs b/src/main.rs
index fe38ec5..1a0b78c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,4 +1,7 @@
 use std::{
+    fs::OpenOptions,
+    io::Write,
+    pin::Pin,
     thread::{spawn, JoinHandle},
     time::Duration,
 };
@@ -10,9 +13,9 @@ struct ProgressCounter(pub *mut u64);
 unsafe impl Send for ProgressCounter {}
 unsafe impl Sync for ProgressCounter {}
 impl ProgressCounter {
-    fn incr(&mut self) {
+    fn incr(&mut self, n: u64) {
         unsafe {
-            *self.0 += 1;
+            *self.0 += n;
         }
     }
 }
@@ -24,49 +27,76 @@ fn work(mut progress: ProgressCounter) -> JoinHandle<()> {
             rand_xoshiro::Xoshiro256StarStar::from_rng(rand::thread_rng()).unwrap()
         };
 
+        const ITERS: u64 = 256;
+
         loop {
-            let key = cpu::generate_privkey(&mut rng);
-            let pub_key = cpu::get_pubkey(&key);
+            for _ in 0..ITERS {
+                let key = cpu::generate_privkey(&mut rng);
+                let pub_key = cpu::get_pubkey(&key);
 
-            progress.incr();
+                // b64(pub_key).starts_with("char") && b64(pub_key)[4] in ["+", "/"]
+                if pub_key[0] == 0x72
+                    && pub_key[1] == 0x16
+                    && pub_key[2] == 0xab
+                    && pub_key[3] >= 0xf8
+                {
+                    let key_str = base64::encode(key);
+                    let pub_key_str = base64::encode(pub_key);
+                    println!("{} -> {}", key_str, pub_key_str);
 
-            // b64(pub_key).starts_with("char/")
-            if pub_key[0] == 0x72 && pub_key[1] == 0x16 && pub_key[2] == 0xab && pub_key[3] >= 0xfc
-            {
-                let key_str = base64::encode(key);
-                let pub_key_str = base64::encode(pub_key);
-                println!("{} -> {}", key_str, pub_key_str);
+                    {
+                        let mut file = OpenOptions::new()
+                            .create(true)
+                            .append(true)
+                            .open("keys.log")
+                            .unwrap();
+
+                        let _ = writeln!(file, "{} -> {}", key_str, pub_key_str);
+                    }
+                }
             }
+
+            progress.incr(ITERS);
         }
     })
 }
 
-const NUM_THREADS: usize = 32;
+const NUM_THREADS: usize = 24;
 
-struct Progress([u64; NUM_THREADS]);
+struct Progress(Pin<Box<[u64; NUM_THREADS]>>);
 impl Progress {
     fn new() -> Self {
-        Progress([0; NUM_THREADS])
+        Progress(Box::pin([0; NUM_THREADS]))
+    }
+
+    unsafe fn the_pointer(&mut self) -> *mut u64 {
+        self.0.as_mut_ptr()
+    }
+
+    fn total(&self) -> u64 {
+        self.0.iter().sum()
     }
 }
 
 fn main() {
-    let mut progress = Box::pin(Progress::new());
+    let mut progress = Progress::new();
     let _handles: Vec<_> = (0..NUM_THREADS)
         .map(|id| {
-            let ptr = unsafe { progress.0.as_mut_ptr().add(id) };
+            let ptr = unsafe { progress.the_pointer().add(id) };
             let progress = ProgressCounter(ptr);
             work(progress)
         })
         .collect();
 
     let mut last_total_progress = 0;
+    let mut sleep_secs = 1.0;
     loop {
-        let total_progress = progress.0.iter().sum();
+        let total_progress = progress.total();
         let delta = total_progress - last_total_progress;
         last_total_progress = total_progress;
 
-        println!("Guess/sec ≈ {}", delta);
-        std::thread::sleep(Duration::from_millis(1000));
+        println!("Guesses/sec ≈ {:.0}", delta as f64 / sleep_secs);
+        std::thread::sleep(Duration::from_secs_f64(sleep_secs));
+        sleep_secs *= 1.05;
     }
 }