Re: [libvirt] [PATCH 2/2] qemu: add a max_core setting to qemu.conf for core dump size

On 03/18/2015 08:36 AM, Daniel P. Berrange wrote: > Currently the QEMU processes inherit their core dump rlimit > from libvirtd, which is really suboptimal. This change allows > their limit to be directly controller from qemu.conf instead. > --- > src/libvirt_private.syms | 2 ++ > src/qemu/libvirtd_qemu.aug | 1 + > src/qemu/qemu.conf | 12 ++++++++++++ > src/qemu/qemu_conf.c | 3 +++ > src/qemu/qemu_conf.h | 2 ++ > src/qemu/qemu_process.c | 2 ++ > src/qemu/test_libvirtd_qemu.aug.in | 1 + > src/util/vircommand.c | 14 ++++++++++++++ > src/util/vircommand.h | 1 + > src/util/virprocess.c | 35 +++++++++++++++++++++++++++++++++++ > src/util/virprocess.h | 1 + > 11 files changed, 74 insertions(+) > > diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms > index ca3520d..7446357 100644 > --- a/src/libvirt_private.syms > +++ b/src/libvirt_private.syms > @@ -1240,6 +1240,7 @@ virCommandSetErrorFD; > virCommandSetGID; > virCommandSetInputBuffer; > virCommandSetInputFD; > +virCommandSetMaxCoreSize; > virCommandSetMaxFiles; > virCommandSetMaxMemLock; > virCommandSetMaxProcesses; > @@ -1951,6 +1952,7 @@ virProcessRunInMountNamespace; > virProcessSchedPolicyTypeFromString; > virProcessSchedPolicyTypeToString; > virProcessSetAffinity; > +virProcessSetMaxCoreSize; > virProcessSetMaxFiles; > virProcessSetMaxMemLock; > virProcessSetMaxProcesses; > diff --git a/src/qemu/libvirtd_qemu.aug b/src/qemu/libvirtd_qemu.aug > index 62951da..029a55a 100644 > --- a/src/qemu/libvirtd_qemu.aug > +++ b/src/qemu/libvirtd_qemu.aug > @@ -71,6 +71,7 @@ module Libvirtd_qemu = > | bool_entry "set_process_name" > | int_entry "max_processes" > | int_entry "max_files" > + | int_entry "max_core" > > let device_entry = bool_entry "mac_filter" > | bool_entry "relaxed_acs_check" > diff --git a/src/qemu/qemu.conf b/src/qemu/qemu.conf > index 1c589a2..12e4326 100644 > --- a/src/qemu/qemu.conf > +++ b/src/qemu/qemu.conf > @@ -390,6 +390,18 @@ > #max_processes = 0 > #max_files = 0 > > +# If max_core is set to a positive integer, then QEMU will be > +# permitted to create core dumps when it crashes, provided its > +# RAM size is smaller than the limit set. Be warned that the > +# core dump will include a full copy of the guest RAM, so if > +# the largest guest is 32 GB in size, the max_core limit will > +# have to be at least 33/34 GB to allow enough overhead. > +# > +# By default it will inherit core limit from libvirtd, which > +# is usually set to 0 by systemd/init. > +# > +# Size is in bytes > +#max_core = 0 It's too bad it cannot be a "sized" value... Reading 20G in a file for me is so much easier than the comparable byte value say nothing if we get to 128G, 1T, etc. (some day).