Android4.0のビルドには冷却能力にも注意を
Android 4.0を full-eng でフルビルドすると
make -j8
real 35m52.527s user 263m34.080s sys 14m40.810s
dmesgでカーネルのログを見るとこんなメッセージが。
[1482147.551197] CPU5: Temperature above threshold, cpu clock throttled (total events = 470039) [1482147.551200] CPU1: Temperature above threshold, cpu clock throttled (total events = 470039) [1482147.552197] CPU1: Temperature/speed normal [1482147.552199] CPU5: Temperature/speed normal [1482447.871374] CPU1: Temperature above threshold, cpu clock throttled (total events = 498371) [1482447.871377] CPU5: Temperature above threshold, cpu clock throttled (total events = 498371) [1482447.872375] CPU5: Temperature/speed normal [1482447.872377] CPU1: Temperature/speed normal [1482751.656890] CPU5: Temperature above threshold, cpu clock throttled (total events = 509239) [1482751.656893] CPU1: Temperature above threshold, cpu clock throttled (total events = 509239) [1482751.657890] CPU5: Temperature/speed normal [1482751.657891] CPU1: Temperature/speed normal [1483051.832731] CPU1: Temperature above threshold, cpu clock throttled (total events = 525120) [1483051.832734] CPU5: Temperature above threshold, cpu clock throttled (total events = 525120) [1483051.833730] CPU1: Temperature/speed normal [1483051.833732] CPU5: Temperature/speed normal [1483413.789544] CPU1: Temperature above threshold, cpu clock throttled (total events = 535518) [1483413.789547] CPU5: Temperature above threshold, cpu clock throttled (total events = 535518) [1483413.790545] CPU5: Temperature/speed normal [1483413.790547] CPU1: Temperature/speed normal [1483715.174854] CPU5: Temperature above threshold, cpu clock throttled (total events = 535567) [1483715.174857] CPU1: Temperature above threshold, cpu clock throttled (total events = 535567) [1483715.175855] CPU5: Temperature/speed normal [1483715.175857] CPU1: Temperature/speed normal
私のビルド環境は Ubuntu 10.04 (x86_64), CPU: Intel Core i7 950 @3.07GHz, メモリ 24GB です。
ケースは上がメッシュになっているタワー型のもの。ディスプレイはつながないでssh経由で使用します。グラフィックボードはファンレスのものをつけてます。(何かつけないと起動時のチェックでひっかかるから。）
CPUのファンはケチってリテール販売のCPUに付属していたものを使っているけど、どうやらそれでは冷却能力が足りないようです。
