diff --git a/samply-symbols/src/breakpad/index.rs b/samply-symbols/src/breakpad/index.rs
index f4ab7627..5d31abad 100644
--- a/samply-symbols/src/breakpad/index.rs
+++ b/samply-symbols/src/breakpad/index.rs
@@ -431,7 +431,7 @@ impl<'a> StringListRef<'a> {
     pub fn as_slice(&self) -> &'a [StringLocation] {
         self.inner
     }
-    pub fn get<R: ReadRef<'a>>(&self, index: u32, data: R) -> Option<&'a [u8]> {
+    pub fn get<'d, R: ReadRef<'d>>(&self, index: u32, data: R) -> Option<&'d [u8]> {
         let location = *self.inner.get(usize::try_from(index).ok()?)?;
         location.get(data)
     }
diff --git a/samply-symbols/src/breakpad/symbol_map.rs b/samply-symbols/src/breakpad/symbol_map.rs
index ca1b1218..02d2025d 100644
--- a/samply-symbols/src/breakpad/symbol_map.rs
+++ b/samply-symbols/src/breakpad/symbol_map.rs
@@ -202,18 +202,6 @@ impl<'a> BreakpadSymbolMapSymbolCache<'a> {
     }
 }
 
-// let file_offset = entry.offset.get();
-// let line_length = entry.line_len.get();
-// let line = self
-//     .data
-//     .read_bytes_at(file_offset, line_length.into())
-//     .map_err(|e| {
-//         Error::HelperErrorDuringFileReading(
-//             "Breakpad FILE or INLINE_ORIGIN record".to_string(),
-//             e,
-//         )
-//     })?;
-
 impl<'object, T: FileContents> SymbolMapTrait for BreakpadSymbolMapInner<'object, T> {
     fn debug_id(&self) -> debugid::DebugId {
         self.index.debug_id
diff --git a/samply/src/shared/presymbolicate.rs b/samply/src/shared/presymbolicate.rs
index 122a6cd5..5497c0d7 100644
--- a/samply/src/shared/presymbolicate.rs
+++ b/samply/src/shared/presymbolicate.rs
@@ -8,8 +8,7 @@ use fxprof_processed_profile::symbol_info::{
 };
 use fxprof_processed_profile::LibraryHandle;
 use rustc_hash::FxHashMap;
-use wholesym::samply_symbols::SourceFilePathHandle;
-use wholesym::{SymbolManager, SymbolMap};
+use wholesym::{SourceFilePathHandle, SymbolManager, SymbolMap};
 
 use crate::symbols::create_symbol_manager_and_quota_manager;
 
diff --git a/samply/src/shared/symbol_precog.rs b/samply/src/shared/symbol_precog.rs
index adc3e949..de328f60 100644
--- a/samply/src/shared/symbol_precog.rs
+++ b/samply/src/shared/symbol_precog.rs
@@ -5,10 +5,7 @@ use std::{borrow::Cow, fs::File};
 
 use serde::de::{Deserialize, Deserializer};
 use serde_derive::Deserialize;
-use wholesym::{
-    samply_symbols::{SourceFilePathHandle, SourceFilePathIndex, SymbolMapGeneration},
-    SourceFilePath,
-};
+use wholesym::{SourceFilePath, SourceFilePathHandle, SourceFilePathIndex, SymbolMapGeneration};
 
 #[derive(Debug, Copy, Clone, PartialOrd, Ord, PartialEq, Eq, Hash)]
 struct StringTableIndex(usize);
diff --git a/wholesym/src/breakpad.rs b/wholesym/src/breakpad.rs
index 31ced0b1..7f2666da 100644
--- a/wholesym/src/breakpad.rs
+++ b/wholesym/src/breakpad.rs
@@ -1,3 +1,4 @@
+use std::io::Read;
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
 
@@ -284,25 +285,28 @@ impl BreakpadSymbolDownloaderInner {
         &self,
         sym_path: &Path,
     ) -> Result<OwnedBreakpadIndex, SymindexGenerationError> {
-        let mut sym_file = tokio::fs::File::open(sym_path)
-            .await
-            .map_err(SymindexGenerationError::SymReading)?;
-        let mut parser = BreakpadIndexCreator::new();
-        const CHUNK_SIZE: usize = 2 * 1024 * 1024; // 2 MiB
-        let mut buffer = vec![0; CHUNK_SIZE];
-        loop {
-            let read_len = sym_file
-                .read(&mut buffer)
-                .await
-                .map_err(SymindexGenerationError::SymReading)?;
-            if read_len == 0 {
-                break;
+        let sym_path = sym_path.to_path_buf();
+        tokio::task::spawn_blocking(|| {
+            let mut sym_file =
+                std::fs::File::open(sym_path).map_err(SymindexGenerationError::SymReading)?;
+            let mut parser = BreakpadIndexCreator::new();
+            const CHUNK_SIZE: usize = 64 * 1024; // 64 KiB
+            let mut buffer = vec![0; CHUNK_SIZE];
+            loop {
+                let read_len = sym_file
+                    .read(&mut buffer)
+                    .map_err(SymindexGenerationError::SymReading)?;
+                if read_len == 0 {
+                    break;
+                }
+                parser.consume(&buffer[..read_len]);
             }
-            parser.consume(&buffer[..read_len]);
-        }
-        parser
-            .finish()
-            .map_err(SymindexGenerationError::BreakpadParsing)
+            parser
+                .finish()
+                .map_err(SymindexGenerationError::BreakpadParsing)
+        })
+        .await
+        .unwrap()
     }
 }
 
diff --git a/wholesym/src/lib.rs b/wholesym/src/lib.rs
index 65d41ad5..ec60e453 100644
--- a/wholesym/src/lib.rs
+++ b/wholesym/src/lib.rs
@@ -153,8 +153,8 @@ pub use samply_symbols;
 pub use samply_symbols::{
     AddressInfo, CodeId, ElfBuildId, Error, ExternalFileAddressInFileRef, ExternalFileAddressRef,
     ExternalFileRef, ExternalFileSymbolMap, FrameDebugInfo, FramesLookupResult, LibraryInfo,
-    LookupAddress, MappedPath, MultiArchDisambiguator, PeCodeId, SourceFilePath, SymbolInfo,
-    SyncAddressInfo,
+    LookupAddress, MappedPath, MultiArchDisambiguator, PeCodeId, SourceFilePath,
+    SourceFilePathHandle, SourceFilePathIndex, SymbolInfo, SymbolMapGeneration, SyncAddressInfo,
 };
 pub use symbol_manager::{SymbolFileOrigin, SymbolManager, SymbolMap};
 pub use symbol_manager_observer::SymbolManagerObserver;