5:46 a.m.
Sorry , clarification:
Bottom line is that the Java binding of libvirt should accept 'dname'
parameter = null as the C libvirt case does without crashing
The below stament that
" If I try to specify a meaningful 'dname' then if it is the same name
as the original host domain 'name' I will get a message saying : invalid
domain pointer in no domain with matching id -1."
is not correct. The migrate works under Java in this case as in the C
case i.e the domain is migrated to the destination
host but remains paused there for a long time until resumed there.
If the 'dname' is null then the migration is faster but that works ok only
with the libvirt C library. It crashes with the Java binding .
Zvi Dubitzky
Virtualization and System Architecture Email:dubi@il.ibm.com
IBM Haifa Research Laboratory Phone: +972-4-8296182
Haifa, 31905, ISRAEL
----- Forwarded by Zvi Dubitzky/Haifa/IBM on 10/05/2009 13:29 -----
Zvi Dubitzky/Haifa/IBM
10/05/2009 13:14
To
libvir-list(a)redhat.com
cc
Subject
Fw: Java api for domain migration
Hi
I think I detected the origin of the libvirt Java binding crash in the
case of domain migration though I do not know how to fix it yet .
The fix should be in the src/jni/org_libvirt_Domain.c / migrate function.
First: It turns out the that the C libvirt interface for migrate (
libvirt 0.6.1. + kvm-84) has a limitation with specifying the 'dname'
parameter . It should be NULL to work ok , meaning the domain is migrated
from the old host to the new host under the same domain name . If I try to
specify a meaningful 'dname' then if it is the same name as the original
host domain 'name' I will get a message saying : invalid domain pointer
in no domain with matching id -1.
If I am using 'dname' different than the original host domain 'name' it
will complain that no such domain is found on the target host.
So using NULL for 'dname' is the only one that makes the migrate work
Using 'dname' = NULL with the Java binding causes it though to crash as
below (see .log file). Fixing the jni code as below (see added 'if') does
not
help:
src/jni/org_libvirt_Domain.c
--------------------------------
JNIEXPORT jlong JNICALL Java_org_libvirt_Domain__1migrate
(JNIEnv *env, jobject obj, jlong VDP, jobject dconn, jlong flags,
jstring j_dname, jstring j_uri, jlong bandwidth){
virConnectPtr destVCP;
const char *dname=NULL;
const char *uri=NULL;
//if String="", we pass NULL to the library
if((*env)->GetStringLength(env, j_dname)>0)
dname=(*env)->GetStringUTFChars(env, j_dname, NULL);
//if String="", we pass NULL to the library
if((*env)->GetStringLength(env, j_uri)>0)
uri=(*env)->GetStringUTFChars(env, j_uri, NULL);
//Extract the destination Conn Ptr
destVCP=(virConnectPtr)(*env)->GetLongField(env, dconn,
(*env)->GetFieldID(env,
(*env)->GetObjectClass(env, dconn), "VCP", "J"));
jlong retval = (jlong)virDomainMigrate((virDomainPtr)VDP, destVCP,
flags, dname, uri, bandwidth)
;
if (dname)
(*env)->ReleaseStringUTFChars(env, j_dname, dname);
if (uri)
(*env)->ReleaseStringUTFChars(env, j_uri, uri);
return retval;
}
Please your advice on how to solve the migrate for the Java binding
thanks
Zvi Dubitzky
Virtualization and System Architecture Email:dubi@il.ibm.com
IBM Haifa Research Laboratory Phone: +972-4-8296182
Haifa, 31905, ISRAEL
----- Forwarded by Zvi Dubitzky/Haifa/IBM on 10/05/2009 12:59 -----
Zvi Dubitzky/Haifa/IBM
07/05/2009 13:49
To
libvir-list(a)redhat.com
cc
Subject
Java api for libvirt migration
I am trying to do a migrate of VM with libvirt 0.6.1 and kvm-84 . I am
successful in doing it many times via the C interface .
I can do most of the basic libvirt activity via the libvirt JAVA library
(libvirt-java-0.2.1). When it comes to a migrate the JVM fails wit a log
file
attached below . Can someone help. My memory consumption in my JAVA test
code is small.
The migrate parameters I am sending with the Java are identical to
those I use in the C case and is:
destDomain = localDomain.migrate (dcon, // destination
host Connect object
VIR_MIGRATE_LIVE,
null, //const char *dname
destination domain name
target_uri,
//"tcp:9.148.28.13:4444"
0 //
unsigned long bandwidth) - do not specify
);
thanks
Zvi Dubitzky
Virtualization and System Architecture Email:dubi@il.ibm.com
IBM Haifa Research Laboratory Phone: +972-4-8296182
Haifa, 31905, ISRAEL