From c82a9a0340bc03bc4aa4fe1cf2d667617371f558 Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Wed, 14 Jan 2015 01:32:11 +0100 Subject: [PATCH] AIO: Reduce number of threads for 32bit hosts On hosts with limited virtual address space (32bit pointers), we can very easily run out of virtual memory with big thread pools. Instead, we should limit ourselves to small pools to keep memory footprint low on those systems. This patch fixes random VM stalls like (process:25114): GLib-ERROR **: gmem.c:103: failed to allocate 1048576 bytes on 32bit ARM systems for me. Signed-off-by: Alexander Graf --- util/thread-pool.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/util/thread-pool.c b/util/thread-pool.c index 610646d131..2e34e9846d 100644 --- a/util/thread-pool.c +++ b/util/thread-pool.c @@ -308,7 +308,12 @@ static void thread_pool_init_one(ThreadPool *pool, AioContext *ctx) qemu_mutex_init(&pool->lock); qemu_cond_init(&pool->worker_stopped); qemu_sem_init(&pool->sem, 0); - pool->max_threads = 64; + if (sizeof(pool) == 4) { + /* 32bit systems run out of virtual memory quickly */ + pool->max_threads = 4; + } else { + pool->max_threads = 64; + } pool->new_thread_bh = aio_bh_new(ctx, spawn_thread_bh_fn, pool); QLIST_INIT(&pool->head);