From 2563bca11544361dc2afa5e20b5663e10a0715cb Mon Sep 17 00:00:00 2001 From: Mike Latimer Date: Fri, 30 Jan 2015 14:01:00 -0700 Subject: [PATCH] libxl: Wait for ballooning if free memory is increasing During domain startup, all required memory ballooning must complete within a maximum window of 33 seconds (3 retries, 11 seconds of delay). If not, domain creation is aborted with a 'failed to free memory' error. In order to accommodate large domains or slower hardware (which require substantially longer to balloon memory) the free memory process should continue retrying if the amount of free memory is increasing on each iteration of the loop. Signed-off-by: Mike Latimer Acked-by: Ian Campbell --- tools/libxl/xl_cmdimpl.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c index b7eac2940c..440db7800c 100644 --- a/tools/libxl/xl_cmdimpl.c +++ b/tools/libxl/xl_cmdimpl.c @@ -2198,8 +2198,9 @@ static int preserve_domain(uint32_t *r_domid, libxl_event *event, static int freemem(uint32_t domid, libxl_domain_build_info *b_info) { - int rc, retries = 3; - uint32_t need_memkb, free_memkb; + int rc, retries; + const int MAX_RETRIES = 3; + uint32_t need_memkb, free_memkb, free_memkb_prev = 0; if (!autoballoon) return 0; @@ -2208,6 +2209,7 @@ static int freemem(uint32_t domid, libxl_domain_build_info *b_info) if (rc < 0) return rc; + retries = MAX_RETRIES; do { rc = libxl_get_free_memory(ctx, &free_memkb); if (rc < 0) @@ -2232,7 +2234,16 @@ static int freemem(uint32_t domid, libxl_domain_build_info *b_info) if (rc < 0) return rc; - retries--; + /* + * If the amount of free mem has increased on this iteration (i.e. + * some progress has been made) then reset the retry counter. + */ + if (free_memkb > free_memkb_prev) { + retries = MAX_RETRIES; + free_memkb_prev = free_memkb; + } else { + retries--; + } } while (retries > 0); return ERROR_NOMEM; -- 2.30.2