stellar · dmkozh · Apr 3, 2026 · Apr 10, 2026 · Apr 10, 2026 · Apr 10, 2026
diff --git a/bench/disable_meta-20260410-205536/results.csv b/bench/disable_meta-20260410-205536/results.csv
@@ -0,0 +1,7 @@
+scenario,median_time_ms,p95_time_ms,p99_time_ms
+"sac,TX=3200,T=1",337.0062885000008,388.6413382500008,449.63406636999326
+"sac,TX=3200,T=8",234.05063849999988,256.48933750000083,264.29044799000235
+"custom_token,TX=1600,T=1",310.4716815000029,334.2666388999983,343.7057104299992
+"custom_token,TX=1600,T=8",159.46541449999904,179.4608217500015,195.17456334999972
+"soroswap,TX=1000,T=1",444.1408194999967,479.7950516499987,504.93647869998614
+"soroswap,TX=1000,T=8",170.7175889999994,191.4872912999981,200.91390174999842
diff --git a/bench/disable_meta-20260410-205536/stamp b/bench/disable_meta-20260410-205536/stamp
@@ -0,0 +1,61 @@
+Warning: running non-release version v26.0.0-62-g0ad388f96 of stellar-core
+v26.0.0-62-g0ad388f96
+ledger protocol version: 26
+rust version: rustc 1.88.0 (6b00bc388 2025-06-23)
+soroban-env-host versions: 
+    host[0]:
+        package version: 21.2.2
+        git version: 7eeddd897cfb0f700f938b0c8d6f0541150d1fcb
+        ledger protocol version: 21
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 21.2.0
+            git version: 9bea881f2057e412fdbb98875841626bf77b4b88
+            base XDR git version: 70180d5e8d9caee9e8645ed8a38c36a8cf403cd9
+    host[1]:
+        package version: 22.0.0
+        git version: 1cd8b8dca9aeeca9ce45b129cd923992b32dc258
+        ledger protocol version: 22
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 22.0.0
+            git version: 715003372ea6380044b5a4a02907ff73e56ae9e7
+            base XDR git version: 529d5176f24c73eeccfa5eba481d4e89c19b1181
+    host[2]:
+        package version: 23.0.0
+        git version: 688bc34e6cd15c71742139e625268c7f30f55a92
+        ledger protocol version: 23
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 23.0.0
+            git version: e83a6337204ecfdb0ac0d44ffb857130c1249b1b
+            base XDR git version: 4b7a2ef7931ab2ca2499be68d849f38190b443ca
+    host[3]:
+        package version: 24.0.0
+        git version: a37eeda815e626f416eff13f2eacb32a8b0c3729
+        ledger protocol version: 24
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 24.0.0
+            git version: 07b765d3ab146f7f7ea951af1f9e41e0ece8fb48
+            base XDR git version: 4b7a2ef7931ab2ca2499be68d849f38190b443ca
+    host[4]:
+        package version: 25.0.0
+        git version: 6323c1fc03ecb9f53b7c1e42fd62c1bbd3aebc2c
+        ledger protocol version: 25
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 25.0.0
+            git version: dc9f40fcb83c3054341f70b65a2222073369b37b
+            base XDR git version: 0a621ec7811db000a60efae5b35f78dee3aa2533
+    host[5]:
+        package version: 26.0.0
+        git version: b351f88a468d3b9e1d6de53d5b0ca585f6b7dadb
+        ledger protocol version: 26
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 26.0.0
+            git version: dd7a165a193126fd37a751d867bee1cb8f3b55a6
+            base XDR git version: cff714a5ebaaaf2dac343b3546c2df73f0b7a36e
+
+Benchmark ledgers=200
diff --git a/bench/p26_baseline_again-20260410-193305/results.csv b/bench/p26_baseline_again-20260410-193305/results.csv
@@ -0,0 +1,7 @@
+scenario,median_time_ms,p95_time_ms,p99_time_ms
+"sac,TX=3200,T=1",348.6932005000017,395.12184564999995,409.27602225000237
+"sac,TX=3200,T=8",242.59525600000052,266.3564931000006,277.14852171
+"custom_token,TX=1600,T=1",310.3890900000006,343.3200991000005,352.79791974000204
+"custom_token,TX=1600,T=8",163.62422350000043,180.21471705000042,187.8724304600013
+"soroswap,TX=1000,T=1",469.7830955000027,495.3508111500008,504.3309423599958
+"soroswap,TX=1000,T=8",183.22680400000036,199.4422209999998,211.36548991000078
diff --git a/bench/p26_baseline_again-20260410-193305/stamp b/bench/p26_baseline_again-20260410-193305/stamp
@@ -0,0 +1,61 @@
+Warning: running non-release version v26.0.0-60-g8c7d5ef0b-dirty of stellar-core
+v26.0.0-60-g8c7d5ef0b-dirty
+ledger protocol version: 26
+rust version: rustc 1.88.0 (6b00bc388 2025-06-23)
+soroban-env-host versions: 
+    host[0]:
+        package version: 21.2.2
+        git version: 7eeddd897cfb0f700f938b0c8d6f0541150d1fcb
+        ledger protocol version: 21
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 21.2.0
+            git version: 9bea881f2057e412fdbb98875841626bf77b4b88
+            base XDR git version: 70180d5e8d9caee9e8645ed8a38c36a8cf403cd9
+    host[1]:
+        package version: 22.0.0
+        git version: 1cd8b8dca9aeeca9ce45b129cd923992b32dc258
+        ledger protocol version: 22
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 22.0.0
+            git version: 715003372ea6380044b5a4a02907ff73e56ae9e7
+            base XDR git version: 529d5176f24c73eeccfa5eba481d4e89c19b1181
+    host[2]:
+        package version: 23.0.0
+        git version: 688bc34e6cd15c71742139e625268c7f30f55a92
+        ledger protocol version: 23
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 23.0.0
+            git version: e83a6337204ecfdb0ac0d44ffb857130c1249b1b
+            base XDR git version: 4b7a2ef7931ab2ca2499be68d849f38190b443ca
+    host[3]:
+        package version: 24.0.0
+        git version: a37eeda815e626f416eff13f2eacb32a8b0c3729
+        ledger protocol version: 24
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 24.0.0
+            git version: 07b765d3ab146f7f7ea951af1f9e41e0ece8fb48
+            base XDR git version: 4b7a2ef7931ab2ca2499be68d849f38190b443ca
+    host[4]:
+        package version: 25.0.0
+        git version: 6323c1fc03ecb9f53b7c1e42fd62c1bbd3aebc2c
+        ledger protocol version: 25
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 25.0.0
+            git version: dc9f40fcb83c3054341f70b65a2222073369b37b
+            base XDR git version: 0a621ec7811db000a60efae5b35f78dee3aa2533
+    host[5]:
+        package version: 26.0.0
+        git version: b351f88a468d3b9e1d6de53d5b0ca585f6b7dadb
+        ledger protocol version: 26
+        pre-release version: 0
+        rs-stellar-xdr:
+            package version: 26.0.0
+            git version: dd7a165a193126fd37a751d867bee1cb8f3b55a6
+            base XDR git version: cff714a5ebaaaf2dac343b3546c2df73f0b7a36e
+
+Benchmark ledgers=200
diff --git a/docs/apply-load-benchmark-sac.cfg b/docs/apply-load-benchmark-sac.cfg
@@ -16,6 +16,8 @@ APPLY_LOAD_TIME_WRITES = true
 # eventually, it is useful to disable these when optimizing anything besides
 # the metrics.
 DISABLE_SOROBAN_METRICS_FOR_TESTING = true
+# Disable transaction metadata collection (BUILD_TESTS forces it otherwise)
+DISABLE_TX_META_FOR_TESTING = true
 # Disable metadata output
 METADATA_OUTPUT_STREAM = ""
 # Disable metadata debug
@@ -32,7 +34,7 @@ APPLY_LOAD_LEDGER_MAX_DEPENDENT_TX_CLUSTERS = 1
 # operations are batched for 'classic' transactions.
 # This is useful to reduce the impact of non-env parts of the apply path, e.g.
 # when evaluating the impact of changes to env itself.
-APPLY_LOAD_BATCH_SAC_COUNT = 100
+APPLY_LOAD_BATCH_SAC_COUNT = 1
 
 # Number of ledgers to close for every iteration of search.
 APPLY_LOAD_NUM_LEDGERS = 100

diff --git a/docs/apply-load-benchmark-token.cfg b/docs/apply-load-benchmark-token.cfg
@@ -16,6 +16,8 @@ APPLY_LOAD_TIME_WRITES = true
 # eventually, it is useful to disable these when optimizing anything besides
 # the metrics.
 DISABLE_SOROBAN_METRICS_FOR_TESTING = true
+# Disable transaction metadata collection (BUILD_TESTS forces it otherwise)
+DISABLE_TX_META_FOR_TESTING = true
 # Disable metadata output
 METADATA_OUTPUT_STREAM = ""
 # Disable metadata debug

diff --git a/scripts/run_apply_load_matrix.py b/scripts/run_apply_load_matrix.py
@@ -71,44 +71,40 @@ def summary(self) -> str:
 SCENARIOS: tuple[Scenario, ...] = (
     Scenario(
         model_tx="sac",
-        tx_count=6400,
+        tx_count=3200,
         thread_count=1,
     ),
     Scenario(
         model_tx="sac",
-        tx_count=6400,
+        tx_count=3200,
         thread_count=8,
     ),
     Scenario(
         model_tx="custom_token",
-        tx_count=3000,
+        tx_count=1600,
         thread_count=1,
     ),
     Scenario(
         model_tx="custom_token",
-        tx_count=3000,
+        tx_count=1600,
         thread_count=8,
     ),
     Scenario(
         model_tx="soroswap",
-        tx_count=1600,
+        tx_count=1000,
         thread_count=1,
     ),
     Scenario(
         model_tx="soroswap",
-        tx_count=1600,
+        tx_count=1000,
         thread_count=8,
     ),
 )
 
 
 def validate_scenarios(scenarios: tuple[Scenario, ...]) -> None:
-    seen_identifiers: set[str] = set()
     for scenario in scenarios:
         identifier = scenario.identifier()
-        if identifier in seen_identifiers:
-            raise ValueError(f"Duplicate scenario identifier: {identifier}")
-        seen_identifiers.add(identifier)
 
         if scenario.model_tx != "sac":
             continue

diff --git a/src/ledger/LedgerManagerImpl.cpp b/src/ledger/LedgerManagerImpl.cpp
@@ -1596,8 +1596,9 @@ LedgerManagerImpl::applyLedger(LedgerCloseData const& ledgerData,
     }
 
 #ifdef BUILD_TESTS
-    // We always store the ledgerCloseMeta in tests so we can inspect it.
-    if (!ledgerCloseMeta)
+    // We always store the ledgerCloseMeta in tests so we can inspect it,
+    // unless explicitly disabled for benchmarking.
+    if (!ledgerCloseMeta && !mApp.getConfig().DISABLE_TX_META_FOR_TESTING)
     {
         ledgerCloseMeta = std::make_unique<LedgerCloseMetaFrame>(
             header.current().ledgerVersion);
@@ -2589,7 +2590,10 @@ LedgerManagerImpl::processResultAndMeta(
     {
         auto metaXDR = txMetaBuilder.finalize(result.isSuccess());
 #ifdef BUILD_TESTS
-        mLastLedgerTxMeta.emplace_back(metaXDR);
+        if (!mApp.getConfig().DISABLE_TX_META_FOR_TESTING)
+        {
+            mLastLedgerTxMeta.emplace_back(metaXDR);
+        }
 #endif
 
         ledgerCloseMeta->setTxProcessingMetaAndResultPair(
@@ -2598,8 +2602,11 @@ LedgerManagerImpl::processResultAndMeta(
     else
     {
 #ifdef BUILD_TESTS
-        mLastLedgerTxMeta.emplace_back(
-            txMetaBuilder.finalize(result.isSuccess()));
+        if (!mApp.getConfig().DISABLE_TX_META_FOR_TESTING)
+        {
+            mLastLedgerTxMeta.emplace_back(
+                txMetaBuilder.finalize(result.isSuccess()));
+        }
 #endif
     }
 }
@@ -2645,8 +2652,11 @@ LedgerManagerImpl::applyTransactions(
     bool enableTxMeta = ledgerCloseMeta != nullptr;
 #ifdef BUILD_TESTS
     // In tests we want to always enable tx meta because we store it in
-    // mLastLedgerTxMeta.
-    enableTxMeta = true;
+    // mLastLedgerTxMeta, unless explicitly disabled for benchmarking.
+    if (!mApp.getConfig().DISABLE_TX_META_FOR_TESTING)
+    {
+        enableTxMeta = true;
+    }
 #endif
     std::optional<SorobanNetworkConfig> sorobanConfig;
     if (protocolVersionStartsFrom(ltx.loadHeader().current().ledgerVersion,

diff --git a/src/main/Config.cpp b/src/main/Config.cpp
@@ -172,6 +172,7 @@ Config::Config() : NODE_SEED(SecretKey::random())
     BACKGROUND_OVERLAY_PROCESSING = true;
     PARALLEL_LEDGER_APPLY = true;
     DISABLE_SOROBAN_METRICS_FOR_TESTING = false;
+    DISABLE_TX_META_FOR_TESTING = false;
     BACKGROUND_TX_SIG_VERIFICATION = true;
     BUCKETLIST_DB_INDEX_PAGE_SIZE_EXPONENT = 14; // 2^14 == 16 kb
     BUCKETLIST_DB_INDEX_CUTOFF = 20;             // 20 mb
@@ -1180,6 +1181,10 @@ Config::processConfig(std::shared_ptr<cpptoml::table> t)
                  [&]() {
                      DISABLE_SOROBAN_METRICS_FOR_TESTING = readBool(item);
                  }},
+                {"DISABLE_TX_META_FOR_TESTING",
+                 [&]() {
+                     DISABLE_TX_META_FOR_TESTING = readBool(item);
+                 }},
                 {"EXPERIMENTAL_BACKGROUND_TX_SIG_VERIFICATION",
                  [&]() {
                      CLOG_WARNING(Overlay,

diff --git a/src/main/Config.h b/src/main/Config.h
@@ -550,6 +550,11 @@ class Config : public std::enable_shared_from_this<Config>
     // Disable expensive Soroban metrics for performance testing
     bool DISABLE_SOROBAN_METRICS_FOR_TESTING;
 
+    // Disable transaction metadata collection in test builds for benchmarking.
+    // When true, BUILD_TESTS overrides that force ledgerCloseMeta allocation
+    // and enableTxMeta are suppressed, avoiding significant XDR copy overhead.
+    bool DISABLE_TX_META_FOR_TESTING;
+
     // Batch transactions for flooding purposes (experimental).
     // Has no effect on non-test builds.
     size_t EXPERIMENTAL_TX_BATCH_MAX_SIZE;

diff --git a/src/rust/src/soroban_invoke.rs b/src/rust/src/soroban_invoke.rs
@@ -20,30 +20,8 @@ pub(crate) fn invoke_host_function(
     rent_fee_configuration: CxxRentFeeConfiguration,
     module_cache: &SorobanModuleCache,
 ) -> Result<InvokeHostFunctionOutput, Box<dyn std::error::Error>> {
-    use std::error::Error as StdError;
-    type BoxStdErr = Box<dyn StdError>;
-    type BoxStdErrSend = Box<dyn StdError + Send>;
-    type BoxStdErrSendSync = Box<dyn StdError + Send + Sync>;
-
-    fn sendable_str_err(str: &str) -> BoxStdErrSend {
-        let tmp: BoxStdErrSendSync = Box::from(str);
-        tmp as BoxStdErrSend
-    }
-
     let hm = get_host_module_for_protocol(config_max_protocol, ledger_info.protocol_version)?;
-    // Rust stacks are 2MiB by default, which is a little too small
-    // for comfort; to give ourselves a little more breathing room
-    // against unforeseen bugs we use a 100MiB stack. Unfortunately
-    // there's no easy way to enforce this at the C++ side when the
-    // initial std::async parallel-exec thread is spawned, so we
-    // have to spawn _another_ here. On linux this is fairly fast,
-    // on the order of a ten-ish microseconds.
-    let LARGE_STACK_SIZE: usize = 100 * 1024 * 1024; // 100 MiB
-    let res = std::thread::scope(|scope| {
-        std::thread::Builder::new()
-            .stack_size(LARGE_STACK_SIZE)
-            .spawn_scoped(scope, || {
-                (hm.invoke_host_function)(
+    let res = (hm.invoke_host_function)(
                     enable_diagnostics,
                     instruction_limit,
                     hf_buf,
@@ -57,19 +35,7 @@ pub(crate) fn invoke_host_function(
                     base_prng_seed,
                     &rent_fee_configuration,
                     module_cache,
-                )
-                // Map non-sendable error to sendable for crossing thread boundary.
-                // This is crude but the error is going to be stringified on the
-                // bridge-crossing anyways.
-                .map_err(|e| sendable_str_err(&format!("{e}")))
-            })
-            .map_err(|_| sendable_str_err("spawn_scoped failed"))?
-            .join()
-            .map_err(|_| sendable_str_err("join failed"))?
-    });
-
-    // Map sendable error back to non-sendable -- Rust doesn't do dyn upcasts.
-    let res = res.map_err(|e: BoxStdErrSend| e as BoxStdErr);
+    );
 
     #[cfg(feature = "testutils")]
     crate::soroban_test_extra_protocol::maybe_invoke_host_function_again_and_compare_outputs(