v0.18.23: bump version

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "libfreemkv"
-version = "0.18.15"
+version = "0.18.23"
 edition = "2024"
 rust-version = "1.86"
 license = "AGPL-3.0-only"

src/aacs/keys.rs

@@ -247,6 +247,7 @@ fn validate_processing_key(
 /// Find Verify Media Key Record (type 0x10) in MKB.
 fn mkb_find_mk_dv(mkb: &[u8]) -> Option<[u8; 16]> {
     let mut pos = 0;
+    let mut type10_seen: Vec<(usize, usize)> = Vec::new();
     while pos + 4 <= mkb.len() {
         let rec_type = mkb[pos];
         let rec_len = u32::from_be_bytes([0, mkb[pos + 1], mkb[pos + 2], mkb[pos + 3]]) as usize;
@@ -254,14 +255,32 @@ fn mkb_find_mk_dv(mkb: &[u8]) -> Option<[u8; 16]> {
             break;
         }
 
+        if rec_type == 0x10 {
+            type10_seen.push((pos, rec_len));
+        }
+
         if rec_type == 0x10 && rec_len >= 20 {
             // mk_dv is at offset 4 (after record header)
             let mut dv = [0u8; 16];
             dv.copy_from_slice(&mkb[pos + 4..pos + 20]);
+            tracing::warn!(
+                target: "freemkv::disc",
+                phase = "mkb_mk_dv_found",
+                pos,
+                rec_len,
+                "mk_dv extracted from MKB"
+            );
             return Some(dv);
         }
         pos += rec_len;
     }
+    tracing::warn!(
+        target: "freemkv::disc",
+        phase = "mkb_mk_dv_not_found",
+        type10_seen = ?type10_seen,
+        scanned_bytes = pos,
+        "no 0x10 record with rec_len>=20 found"
+    );
     None
 }
 
@@ -628,32 +647,70 @@ pub fn resolve_keys(
         }
     };
 
+    tracing::warn!(
+        target: "freemkv::disc",
+        phase = "resolve_keys_start",
+        aacs2,
+        bus_encryption,
+        disc_hash = %hash_hex,
+        mkb_present = mkb_data.is_some(),
+        "resolve_keys: starting"
+    );
+
     // Path 1: Look up VUK by disc hash in KEYDB
     if let Some(entry) = keydb.find_disc(&hash_hex) {
+        tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_path1_hit_entry", "disc hash found in keydb");
         if let Some(vuk) = entry.vuk {
             return Some(build(vuk, 1));
         }
+        tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_path1_no_vuk", "disc hash entry has no VUK");
+    } else {
+        tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_path1_miss", "disc hash NOT in keydb");
     }
 
     // Path 2: Find entry with matching VID → derive VUK from MK + VID
+    let mut path2_mk_did_count = 0usize;
     for entry in keydb.disc_entries.values() {
         if let (Some(mk), Some(did)) = (entry.media_key, entry.disc_id) {
+            path2_mk_did_count += 1;
             if did == *volume_id {
+                tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_path2_hit", "MK+VID entry matched volume_id");
                 return Some(build(derive_vuk(&mk, volume_id), 2));
             }
         }
     }
+    tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_path2_miss", mk_did_entries = path2_mk_did_count, "no MK+VID entry matched volume_id");
 
     // Path 3: MKB + processing keys → media key → VUK
     if let Some(mkb) = mkb_data {
+        let mk_dv = mkb_find_mk_dv(mkb);
+        let subdiff = mkb_find_subdiff_records(mkb);
+        let cvalues = mkb_find_cvalues(mkb);
+        tracing::warn!(
+            target: "freemkv::disc",
+            phase = "resolve_keys_mkb_records",
+            mk_dv_found = mk_dv.is_some(),
+            subdiff_found = subdiff.is_some(),
+            subdiff_len = subdiff.as_ref().map(|s| s.len()).unwrap_or(0),
+            cvalues_found = cvalues.is_some(),
+            cvalues_len = cvalues.as_ref().map(|c| c.len()).unwrap_or(0),
+            "MKB record scan results"
+        );
+
         if let Some(mk) = derive_media_key_from_pk(mkb, &keydb.processing_keys) {
+            tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_path3_hit", "media key derived from processing key");
             return Some(build(derive_vuk(&mk, volume_id), 3));
         }
+        tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_path3_miss", pk_count = keydb.processing_keys.len(), "PK derivation failed");
 
         // Path 4: MKB + device keys → processing key → media key → VUK
         if let Some(mk) = derive_media_key_from_dk(mkb, &keydb.device_keys) {
+            tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_path4_hit", "media key derived from device key");
             return Some(build(derive_vuk(&mk, volume_id), 4));
         }
+        tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_path4_miss", dk_count = keydb.device_keys.len(), "DK derivation failed");
+    } else {
+        tracing::warn!(target: "freemkv::disc", phase = "resolve_keys_no_mkb", "no MKB data available; paths 3/4 skipped");
     }
 
     None

src/disc/encrypt.rs

@@ -22,12 +22,27 @@ impl Disc {
     ) -> Option<HandshakeResult> {
         use crate::aacs::{self, KeyDb};
 
-        let keydb_path = opts.resolve_keydb()?;
+        tracing::warn!(
+            target: "freemkv::disc",
+            phase = "handshake_entry",
+            "do_handshake entered"
+        );
+        let keydb_path = match opts.resolve_keydb() {
+            Some(p) => p,
+            None => {
+                tracing::warn!(
+                    target: "freemkv::disc",
+                    phase = "handshake_no_keydb",
+                    "no KEYDB found in search paths; handshake skipped"
+                );
+                return None;
+            }
+        };
         let keydb = match KeyDb::load(&keydb_path) {
             Ok(db) => db,
             Err(e) => {
                 tracing::warn!(
-                    target: "freemkv::aacs",
+                    target: "freemkv::disc",
                     phase = "handshake_keydb_load_failed",
                     io_error_kind = ?e.kind(),
                     keydb = %keydb_path.display(),
@@ -38,11 +53,12 @@ impl Disc {
         };
 
         let host_cert_count = keydb.host_certs.len();
-        tracing::debug!(
-            target: "freemkv::aacs",
+        tracing::warn!(
+            target: "freemkv::disc",
             phase = "handshake_start",
             host_cert_count,
             keydb = %keydb_path.display(),
+            "handshake starting"
         );
 
         const MAX_CERT_ATTEMPTS: usize = 16;
@@ -54,7 +70,7 @@ impl Disc {
                         Ok(vid) => vid,
                         Err(e) => {
                             tracing::warn!(
-                                target: "freemkv::aacs",
+                                target: "freemkv::disc",
                                 phase = "handshake_vid_read_failed",
                                 cert_index = idx,
                                 error_code = e.code(),
@@ -67,7 +83,7 @@ impl Disc {
                         .ok()
                         .map(|(rdk, _)| rdk);
                     tracing::debug!(
-                        target: "freemkv::aacs",
+                        target: "freemkv::disc",
                         phase = "handshake_ok",
                         cert_index = idx,
                         has_read_data_key = read_data_key.is_some(),
@@ -84,7 +100,7 @@ impl Disc {
             }
         }
         tracing::warn!(
-            target: "freemkv::aacs",
+            target: "freemkv::disc",
             phase = "handshake_all_certs_failed",
             host_cert_count,
             tried = host_cert_count.min(MAX_CERT_ATTEMPTS),
@@ -118,6 +134,19 @@ impl Disc {
             .or_else(|_| udf_fs.read_file(reader, "/AACS/DUPLICATE/Unit_Key_RO.inf"))
             .map_err(|_| Error::AacsNoKeys)?;
 
+        // Log the disc hash so we can confirm whether it's present in KEYDB
+        // when key resolution fails. The disc hash is SHA-1 of the full
+        // Unit_Key_RO.inf file bytes — same value KEYDB.cfg keys VUK entries by.
+        let dh = crate::aacs::disc_hash(&uk_ro_data);
+        let dh_hex = crate::aacs::disc_hash_hex(&dh);
+        tracing::warn!(
+            target: "freemkv::disc",
+            phase = "scan_aacs_disc_hash",
+            disc_hash = %dh_hex,
+            uk_ro_len = uk_ro_data.len(),
+            "disc hash computed (compare with keydb.cfg entries)"
+        );
+
         let cc_data = udf_fs
             .read_file(reader, "/AACS/Content000.cer")
             .or_else(|_| udf_fs.read_file(reader, "/AACS/Content001.cer"))
@@ -129,6 +158,28 @@ impl Disc {
             .ok();
         let mkb_ver = mkb_data.as_deref().and_then(aacs::mkb_version);
 
+        let mkb_first_64_hex = mkb_data
+            .as_deref()
+            .map(|m| {
+                m.iter()
+                    .take(64)
+                    .map(|b| format!("{b:02x}"))
+                    .collect::<String>()
+            })
+            .unwrap_or_default();
+        tracing::warn!(
+            target: "freemkv::disc",
+            phase = "scan_aacs_mkb_info",
+            mkb_present = mkb_data.is_some(),
+            mkb_len = mkb_data.as_deref().map(|m| m.len()).unwrap_or(0),
+            mkb_version = ?mkb_ver,
+            mkb_first_64 = %mkb_first_64_hex,
+            keydb_disc_count = keydb.disc_entries.len(),
+            keydb_dk_count = keydb.device_keys.len(),
+            keydb_pk_count = keydb.processing_keys.len(),
+            "AACS resolution inputs"
+        );
+
         // Use handshake volume ID if available, otherwise zeros
         // (KEYDB VUK lookup by disc hash works without volume ID)
         let volume_id = handshake.map(|h| h.volume_id).unwrap_or([0u8; 16]);

src/disc/mod.rs

@@ -1545,7 +1545,7 @@ impl Disc {
         let batch: u16 = match opts.batch_sectors {
             Some(b) => b,
             None if opts.skip_on_error => ecc_sectors(self.format),
-            None => DEFAULT_BATCH_SECTORS,
+            None => DEFAULT_BATCH_SECTORS_OPTICAL,
         };
 
         // Pre-compute the list of NonTried regions before handing the
@@ -3327,7 +3327,8 @@ impl Disc {
 }
 
 const MAX_BATCH_SECTORS: u16 = 510;
-const DEFAULT_BATCH_SECTORS: u16 = 60;
+const DEFAULT_BATCH_SECTORS_OPTICAL: u16 = 60;
+const DEFAULT_BATCH_SECTORS_BLOCK: u16 = 8192;
 const MIN_BATCH_SECTORS: u16 = 3;
 
 pub(crate) fn ecc_sectors(format: DiscFormat) -> u16 {
@@ -3404,43 +3405,63 @@ mod severity_tests {
 }
 
 /// Detect the maximum transfer size in sectors for a device.
-/// Reads /sys/block/<dev>/queue/max_hw_sectors_kb on Linux.
-/// For sg devices, resolves the corresponding block device via sysfs.
-/// Returns a value aligned to 3 sectors (one aligned unit).
 pub fn detect_max_batch_sectors(device_path: &str) -> u16 {
     let dev_name = device_path.rsplit('/').next().unwrap_or("");
     if dev_name.is_empty() {
-        return DEFAULT_BATCH_SECTORS;
+        return DEFAULT_BATCH_SECTORS_OPTICAL;
     }
 
-    // For sg devices, find the corresponding block device name
-    let block_name = if dev_name.starts_with("sg") {
-        let block_dir = format!("/sys/class/scsi_generic/{dev_name}/device/block");
-        std::fs::read_dir(&block_dir)
-            .ok()
-            .and_then(|mut entries| entries.next())
-            .and_then(|e| e.ok())
-            .map(|e| e.file_name().to_string_lossy().to_string())
-    } else {
-        Some(dev_name.to_string())
-    };
-
-    if let Some(bname) = block_name {
-        let sysfs_path = format!("/sys/block/{bname}/queue/max_hw_sectors_kb");
-        if let Ok(content) = std::fs::read_to_string(&sysfs_path) {
-            if let Ok(kb) = content.trim().parse::<u32>() {
-                // Convert KB to sectors (1 sector = 2 KB = 2048 bytes)
-                let sectors = (kb / 2) as u16;
-                // Align down to 3 (one aligned unit)
-                let aligned = (sectors / 3) * 3;
-                if aligned >= MIN_BATCH_SECTORS {
-                    return aligned.min(MAX_BATCH_SECTORS);
+    // Check if optical drive (0x05 = CD/DVD)
+    let is_optical = (|| -> bool {
+        use std::path::Path;
+        let scsi_device_dir = "/sys/class/scsi_device/".to_string();
+        if let Ok(entries) = std::fs::read_dir(&scsi_device_dir) {
+            for entry in entries.flatten() {
+                let device_type_path = entry.path().join("device/type");
+                if Path::new(&device_type_path).exists() {
+                    if let Ok(content) = std::fs::read_to_string(&device_type_path) {
+                        // Type 0x05 (decimal 5) = CD/DVD drive
+                        if content.trim().parse::<u32>() == Ok(5) {
+                            return true;
+                        }
+                    }
                 }
             }
         }
+        false
+    })();
+
+    if is_optical {
+        // For sg devices, find the corresponding block device name
+        let block_name = if dev_name.starts_with("sg") {
+            let block_dir = format!("/sys/class/scsi_generic/{dev_name}/device/block");
+            std::fs::read_dir(&block_dir)
+                .ok()
+                .and_then(|mut entries| entries.next())
+                .and_then(|e| e.ok())
+                .map(|e| e.file_name().to_string_lossy().to_string())
+        } else {
+            Some(dev_name.to_string())
+        };
+
+        if let Some(bname) = block_name {
+            let sysfs_path = format!("/sys/block/{bname}/queue/max_hw_sectors_kb");
+            if let Ok(content) = std::fs::read_to_string(&sysfs_path) {
+                if let Ok(kb) = content.trim().parse::<u32>() {
+                    // Convert KB to sectors (1 sector = 2 KB = 2048 bytes)
+                    let sectors = (kb / 2) as u16;
+                    // Align down to 3 (one aligned unit)
+                    let aligned = (sectors / 3) * 3;
+                    if aligned >= MIN_BATCH_SECTORS {
+                        return aligned.min(MAX_BATCH_SECTORS);
+                    }
+                }
+            }
+        }
+        DEFAULT_BATCH_SECTORS_OPTICAL
+    } else {
+        DEFAULT_BATCH_SECTORS_BLOCK
     }
-    // Fallback: safe default well under typical kernel limits
-    DEFAULT_BATCH_SECTORS
 }
 
 // ─── Format helpers ────────────────────────────────────────────────────────

src/io/mod.rs

@@ -27,5 +27,7 @@ pub(crate) use writeback_file::WritebackFile;
 // caller — the targeted `#[allow]` keeps the re-export visible without
 // dragging the rest of the module under `dead_code`.
 #[allow(unused_imports)]
-pub use pipeline::WRITE_THROUGH_DEPTH;
-pub use pipeline::{DEFAULT_PIPELINE_DEPTH, Flow, Pipeline, Sink};
+pub use pipeline::{
+    DEFAULT_PIPELINE_DEPTH, Flow, Pipeline, READ_PIPELINE_DEPTH, Sink, WRITE_PIPELINE_DEPTH,
+    WRITE_THROUGH_DEPTH,
+};

src/io/pipeline.rs

@@ -27,15 +27,11 @@
 //! - Consumer panic is converted into
 //!   `Error::IoError { source: io::Error::other(...) }`.
 //!
-//! ## Dead-code suppression
+//! ## Debug logging
 //!
-//! Both `Disc::sweep` (`DEFAULT_PIPELINE_DEPTH`, `spawn_named`,
-//! `try_send`) and `Disc::patch` (`WRITE_THROUGH_DEPTH`, `Flow::Stop`)
-//! are now in-tree callers (0.18 round 2). The targeted `#[allow]`
-//! markers below cover the corners of the API not exercised by either
-//! call site (e.g. `Pipeline::spawn` without a name; `Flow::Stop`
-//! return path from sweep's sink — sweep always consumes the producer's
-//! full work-list). Drop the allows once mux migrates.
+//! Set `FREEMKV_DEBUG=1` environment variable to enable verbose debug
+//! logging throughout the pipeline (channel sends/receives, backpressure,
+//! consumer lag detection). This is critical for diagnosing stalls.
 
 use std::io;
 use std::sync::mpsc::{SyncSender, sync_channel};
@@ -43,20 +39,29 @@ use std::thread::{self, JoinHandle};
 
 use crate::error::Error;
 
+/// Check if verbose debug logging is enabled via FREEMKV_DEBUG env var.
+pub fn debug_enabled() -> bool {
+    std::env::var("FREEMKV_DEBUG")
+        .ok()
+        .map(|v| v == "1" || v == "true" || v == "yes")
+        .unwrap_or(false)
+}
+
 /// Default channel depth for callers without a specific reason to
-/// pick another value.
-///
-/// Empirically tuned for sweep and mux — both want enough slack that
-/// short consumer stalls don't immediately back up onto the producer,
-/// but not so much that a producer outpacing the consumer accumulates
-/// arbitrary buffered work. `4` matches the depth sweep has used
-/// since 0.17.11 (originally in `disc/sweep_pipeline.rs`, now in
-/// `disc/sweep.rs::SweepSink`). Patch should usually use
-/// [`WRITE_THROUGH_DEPTH`] (`1`) instead — write-through gives clean
-/// back-pressure between every read attempt and the matching write,
-/// which matters when the consumer is updating the mapfile in lockstep.
+/// pick another value. Kept conservative (4) — most callers should
+/// use READ_PIPELINE_DEPTH or WRITE_PIPELINE_DEPTH instead.
 pub const DEFAULT_PIPELINE_DEPTH: usize = 4;
 
+/// Read pipeline depth. Larger buffer compensates for drive variability
+/// and NFS sync_file_range stalls; keeps ISO reader thread fed even when
+/// consumer blocks on write.
+pub const READ_PIPELINE_DEPTH: usize = 32;
+
+/// Write pipeline depth. Smaller buffer reduces backpressure risk when
+/// sync_file_range blocks; prevents producer from accumulating too much
+/// work while consumer waits for NFS to drain.
+pub const WRITE_PIPELINE_DEPTH: usize = 16;
+
 /// Channel depth for write-through pipelines. Each `send` fully
 /// drains before the next can enqueue. Use this when the producer
 /// must observe consumer side-effects (e.g. mapfile state) before
@@ -149,6 +154,12 @@ impl<I: Send + 'static, R: Send + 'static> Pipeline<I, R> {
                 let mut stopped = false;
 
                 while let Ok(item) = rx.recv() {
+                    if debug_enabled() {
+                        tracing::debug!("Pipeline receive: item={}", std::any::type_name::<I>());
+                    }
+
+                    let apply_start = std::time::Instant::now();
+
                     if first_err.is_some() || stopped {
                         // Drain remaining items so the producer never
                         // blocks on a dead receiver. `apply` is not
@@ -159,11 +170,32 @@ impl<I: Send + 'static, R: Send + 'static> Pipeline<I, R> {
                         Ok(Flow::Continue) => {}
                         Ok(Flow::Stop) => {
                             stopped = true;
+                            if debug_enabled() {
+                                tracing::debug!("Pipeline: consumer returned Flow::Stop");
+                            }
                         }
                         Err(e) => {
+                            if debug_enabled() {
+                                tracing::debug!("Pipeline: apply error, stopping, err={:?}", e);
+                            }
                             first_err = Some(e);
                         }
                     }
+
+                    let apply_elapsed = apply_start.elapsed();
+                    if debug_enabled() && apply_elapsed > std::time::Duration::from_millis(100) {
+                        tracing::debug!(
+                            "Pipeline apply: took {:.2}s, item={}",
+                            apply_elapsed.as_secs_f64(),
+                            std::any::type_name::<I>()
+                        );
+                    } else if debug_enabled() {
+                        tracing::debug!(
+                            "Pipeline apply: OK in {:.3}ms, item={}",
+                            apply_elapsed.as_micros(),
+                            std::any::type_name::<I>()
+                        );
+                    }
                 }
 
                 match first_err {
@@ -188,7 +220,35 @@ impl<I: Send + 'static, R: Send + 'static> Pipeline<I, R> {
     /// independent signal (e.g. `Halt`) — `send` alone is not the
     /// notification edge.
     pub fn send(&self, item: I) -> Result<(), I> {
-        self.tx.send(item).map_err(|e| e.0)
+        let start = std::time::Instant::now();
+        match self.tx.send(item) {
+            Ok(()) => {
+                let elapsed = start.elapsed();
+                if debug_enabled() && elapsed > std::time::Duration::from_millis(10) {
+                    tracing::debug!(
+                        "Pipeline send: blocked {:.2}s, item={}",
+                        elapsed.as_secs_f64(),
+                        std::any::type_name::<I>()
+                    );
+                } else if debug_enabled() {
+                    tracing::debug!("Pipeline send: OK in {:.3}ms", elapsed.as_micros());
+                }
+                Ok(())
+            }
+            Err(e) => {
+                let elapsed = start.elapsed();
+                if debug_enabled() && elapsed > std::time::Duration::from_millis(10) {
+                    tracing::debug!(
+                        "Pipeline send: blocked {:.2}s before channel closed, item={}",
+                        elapsed.as_secs_f64(),
+                        std::any::type_name::<I>()
+                    );
+                } else if debug_enabled() {
+                    tracing::debug!("Pipeline send: failed after {:.3}ms", elapsed.as_micros());
+                }
+                Err(e.0)
+            }
+        }
     }
 
     /// Non-blocking variant of [`Pipeline::send`]. If the channel is

src/io/writeback_file.rs

@@ -27,7 +27,7 @@ use std::path::Path;
 
 use super::writeback::WritebackPipeline;
 
-const CHUNK_BYTES: u64 = 32 * 1024 * 1024;
+const WRITEBACK_CHUNK_BYTES: u64 = 32 * 1024 * 1024;
 
 pub(crate) struct WritebackFile {
     file: File,
@@ -42,7 +42,7 @@ impl WritebackFile {
     /// or appended files).
     pub(crate) fn new(mut file: File) -> io::Result<Self> {
         let pos = file.stream_position()?;
-        let pipeline = WritebackPipeline::new(&file, pos, CHUNK_BYTES);
+        let pipeline = WritebackPipeline::new(&file, pos, WRITEBACK_CHUNK_BYTES);
         Ok(Self {
             file,
             pipeline,

src/lib.rs

@@ -82,7 +82,7 @@ pub mod event;
 pub mod halt;
 pub(crate) mod identity;
 pub(crate) mod ifo;
-pub(crate) mod io;
+pub mod io;
 pub mod keydb;
 pub mod labels;
 pub(crate) mod mpls;
@@ -128,16 +128,19 @@ pub use halt::Halt;
 
 // Generic bounded producer/consumer primitive used by sweep, patch, and
 // mux to overlap reads with writes via a dedicated consumer thread.
-// `Pipeline::spawn(depth, sink)` spawns the consumer; `pipe.send(item)`
+// `Pipeline::spawn(name, depth, sink)` spawns a named consumer; `pipe.send(item)`
 // pushes one item with back-pressure; `pipe.finish()` joins the
 // consumer and surfaces its `close()` output. Callers implement `Sink`
 // to define per-item behaviour and end-of-stream finalisation.
 //
-// `DEFAULT_PIPELINE_DEPTH` (=4) is the depth sweep + mux use; patch
-// uses `WRITE_THROUGH_DEPTH` (=1) so each read fully drains before the
-// next can enqueue. Returning `Flow::Stop` from `apply` ends the
-// consumer cleanly (still calls `close()`).
-pub use io::pipeline::{DEFAULT_PIPELINE_DEPTH, Flow, Pipeline, Sink, WRITE_THROUGH_DEPTH};
+// `DEFAULT_PIPELINE_DEPTH` (=4) is for callers without specific needs;
+// most should use READ_PIPELINE_DEPTH or WRITE_PIPELINE_DEPTH instead.
+// Patch uses `WRITE_THROUGH_DEPTH` (=1). Returning `Flow::Stop` from
+// `apply` ends the consumer cleanly (still calls `close()`).
+pub use io::pipeline::{
+    DEFAULT_PIPELINE_DEPTH, Flow, Pipeline, READ_PIPELINE_DEPTH, Sink, WRITE_PIPELINE_DEPTH,
+    WRITE_THROUGH_DEPTH,
+};
 
 // ─── Drive events (low-level callbacks) ─────────────────────────────────────
 pub use event::{Event, EventKind};

src/mux/resolve.rs

@@ -204,7 +204,11 @@ pub fn input(url: &str, opts: &InputOptions) -> io::Result<Box<dyn crate::pes::S
             let title = disc.titles[idx].clone();
             let keys = disc.decrypt_keys();
             let format = disc.content_format;
-            let mut stream = DiscStream::new(Box::new(reader), title, keys, 64, format);
+            // ISO file: use large batch size (16 MB) — sequential read from fast storage, no bad sectors.
+            // Physical drives need small batches for adaptive error handling and retry logic.
+            const ISO_MUX_BATCH_SECTORS: u16 = 8192;
+            let mut stream =
+                DiscStream::new(Box::new(reader), title, keys, ISO_MUX_BATCH_SECTORS, format);
             if opts.raw {
                 stream.set_raw();
             }