commit 025c7ccde2e4ce056121e01e404bbd9e522b399e
author David Brazdil <dbrazdil@google.com> Mon Feb 06 16:14:23 2023 +0000
committer David Brazdil <dbrazdil@google.com> Mon Feb 06 18:00:35 2023 +0000
tree 3de9d6d69de5a34b9940f7ffb66d50ccdd98da12
parent 6653791e23fe6da27c1c1bb3312d6823a312c30a

composd: Always start VM with numVCpus=numCpus

InstanceManager reads the value of "dalvik.vm.boot-dex2oat-threads" and
if set, configures the VM to have an equivalent number of vCPUs. This is
unnecessary as `odrefresh` does the same inside the VM (the value of the
prop is propagated to the guest). Deduplicate by removing the host-side
configuration.

Test: atest ComposHostTestCases
Change-Id: I2e4547c6ccae506961e2da7c941651d52a6054d8

compos/common/lib.rs

diff --git a/compos/common/lib.rs b/compos/common/lib.rs
index 8d49ff0..1f937c9 100644
--- a/compos/common/lib.rs
+++ b/compos/common/lib.rs
@@ -53,9 +53,6 @@
 /// /system_ext available in CompOS.
 pub const IDSIG_MANIFEST_EXT_APK_FILE: &str = "idsig_manifest_ext_apk";
 
-/// Number of CPUs to run dex2oat (actually the entire compos VM) with
-pub const DEX2OAT_THREADS_PROP_NAME: &str = "dalvik.vm.boot-dex2oat-threads";
-
 /// The Android path of fs-verity build manifest APK for /system.
 pub const BUILD_MANIFEST_APK_PATH: &str = "/system/etc/security/fsverity/BuildManifest.apk";
 

compos/composd/src/instance_manager.rs

diff --git a/compos/composd/src/instance_manager.rs b/compos/composd/src/instance_manager.rs
index c4791e9..0a6c3d6 100644
--- a/compos/composd/src/instance_manager.rs
+++ b/compos/composd/src/instance_manager.rs
@@ -22,10 +22,8 @@
 use anyhow::{bail, Result};
 use binder::Strong;
 use compos_common::compos_client::VmParameters;
-use compos_common::{CURRENT_INSTANCE_DIR, DEX2OAT_THREADS_PROP_NAME, TEST_INSTANCE_DIR};
-use rustutils::system_properties;
+use compos_common::{CURRENT_INSTANCE_DIR, TEST_INSTANCE_DIR};
 use std::num::NonZeroU32;
-use std::str::FromStr;
 use std::sync::{Arc, Mutex, Weak};
 use virtualizationservice::IVirtualizationService::IVirtualizationService;
 
@@ -79,14 +77,10 @@
 }
 
 fn new_vm_parameters() -> Result<VmParameters> {
-    let cpus = match system_properties::read(DEX2OAT_THREADS_PROP_NAME)? {
-        Some(s) => Some(NonZeroU32::from_str(&s)?),
-        None => {
-            // dex2oat uses all CPUs by default. To match the behavior, give the VM all CPUs by
-            // default.
-            NonZeroU32::new(num_cpus::get() as u32)
-        }
-    };
+    // By default, dex2oat starts as many threads as there are CPUs. This can be overridden with
+    // a system property. Start the VM with all CPUs and assume the guest will start a suitable
+    // number of dex2oat threads.
+    let cpus = NonZeroU32::new(num_cpus::get() as u32);
     let task_profiles = vec!["SCHED_SP_COMPUTE".to_string()];
     Ok(VmParameters { cpus, task_profiles, memory_mib: Some(VM_MEMORY_MIB), ..Default::default() })
 }