search for: vixdisklib_close

I believe this roughly implements Nir's proposal here: https://www.redhat.com/archives/libguestfs/2020-August/msg00028.html Unfortunately it doesn't work for me. It actually slows things down quite a lot, for reasons I don't understand. Note the adjustment of the pool-max parameter and how it affects the total time. The results are quite reproducible. $ ./nbdkit -r -U - vddk

...rr2; + } + + nbdkit_debug ("transport mode for single_link: %s", + VixDiskLib_GetTransportMode (h->handle_single_link)); + } + return h; err2: @@ -559,6 +573,10 @@ vddk_close (void *handle) free_connect_params (h->params); DEBUG_CALL ("VixDiskLib_Close", "handle"); VixDiskLib_Close (h->handle); + if (single_link) { + DEBUG_CALL ("VixDiskLib_Close", "handle_single_link"); + VixDiskLib_Close (h->handle_single_link); + } DEBUG_CALL ("VixDiskLib_Disconnect", "connection");...

...s/11750/virtual-disk-development-kit-programming-guide/GUID-6BE903E8-DC70-46D9-98E4-E34A2002C2AD.html > + * > + * Before nbdkit 1.22 we used SERIALIZE_ALL_REQUESTS. Since nbdkit > + * 1.22 we changed this to SERIALIZE_REQUESTS and added a mutex around > + * calls to VixDiskLib_Open and VixDiskLib_Close. This is not quite > + * within the letter of the rules, but is within the spirit. > The document is very clear about using the same thread for open an close. Using a lock is not the same. I think Eric already wrote about this. */ > -#define THREAD_MODEL NBDKIT_THREAD_MODEL_SERIALIZE...

.../code.vmware.com/docs/11750/virtual-disk-development-kit-programming-guide/GUID-6BE903E8-DC70-46D9-98E4-E34A2002C2AD.html * * Before nbdkit 1.22 we used SERIALIZE_ALL_REQUESTS. Since nbdkit - * 1.22 we changed this to SERIALIZE_REQUESTS and added a mutex around - * calls to VixDiskLib_Open and VixDiskLib_Close. This is not quite - * within the letter of the rules, but is within the spirit. + * 1.22 we changed this to PARALLEL, added a mutex around calls to + * VixDiskLib_Open and VixDiskLib_Close, and use a pool of disk + * handles. This is not quite within the letter of the rules, but is + * within th...

...s/11750/virtual-disk-development-kit-programming-guide/GUID-6BE903E8-DC70-46D9-98E4-E34A2002C2AD.html > * > * Before nbdkit 1.22 we used SERIALIZE_ALL_REQUESTS. Since nbdkit > - * 1.22 we changed this to SERIALIZE_REQUESTS and added a mutex around > - * calls to VixDiskLib_Open and VixDiskLib_Close. This is not quite > - * within the letter of the rules, but is within the spirit. > + * 1.22 we changed this to PARALLEL, added a mutex around calls to > + * VixDiskLib_Open and VixDiskLib_Close, and use a pool of disk > + * handles. This is not quite within the letter of the rules,...

We had a query yesterday about the VDDK plugin and making it actually obey the weird "Multithreading Considerations" rules in the VDDK documentation (https://vdc-download.vmware.com/vmwb-repository/dcr-public/8f96698a-0e7b-4d67-bb6c-d18a1d101540/ef536a47-27cd-481a-90ef-76b38e75353c/vsphere-vddk-671-programming-guide.pdf) This patch is my attempt to implement this. The idea is that the

Couple of fixes to return correct data and one nice-to-have clean-up which is not needed. I just find it nicer to read. Martin Kletzander (3): vddk: Use a separate handle for single-link=true vddk: Do not report hole extents to be zero with single-link=true vddk: Eliminate one needless goto plugins/vddk/vddk.c | 48 +++++++++++++++++++++++++++++++++------------ 1 file changed, 36

.../code.vmware.com/docs/11750/virtual-disk-development-kit-programming-guide/GUID-6BE903E8-DC70-46D9-98E4-E34A2002C2AD.html + * + * Before nbdkit 1.22 we used SERIALIZE_ALL_REQUESTS. Since nbdkit + * 1.22 we changed this to SERIALIZE_REQUESTS and added a mutex around + * calls to VixDiskLib_Open and VixDiskLib_Close. This is not quite + * within the letter of the rules, but is within the spirit. + * + * We also enabled multi-conn for readonly connections since it + * appears possible for clients to open multiple handles even if they + * point to the same server/disk. */ -#define THREAD_MODEL NBDKIT_THREAD_M...

.../code.vmware.com/docs/11750/virtual-disk-development-kit-programming-guide/GUID-6BE903E8-DC70-46D9-98E4-E34A2002C2AD.html + * + * Before nbdkit 1.22 we used SERIALIZE_ALL_REQUESTS. Since nbdkit + * 1.22 we changed this to SERIALIZE_REQUESTS and added a mutex around + * calls to VixDiskLib_Open and VixDiskLib_Close. This is not quite + * within the letter of the rules, but is within the spirit. */ -#define THREAD_MODEL NBDKIT_THREAD_MODEL_SERIALIZE_ALL_REQUESTS +#define THREAD_MODEL NBDKIT_THREAD_MODEL_SERIALIZE_REQUESTS + +/* Lock protecting open/close calls - see above. */ +static pthread_mutex_t open_cl...

In theory this patch depends on this series: https://www.redhat.com/archives/libguestfs/2020-August/msg00021.html In practice I believe they're independent of each other, but the above series makes it easier to test. Rich.

This is my second attempt at this. The first version (also not working) was here: https://www.redhat.com/archives/libguestfs/2019-October/msg00062.html In part 1/2 I introduce a new .ready_to_serve plugin method which is called after forking and just before accepting any client connection. The idea would be that plugins could start background threads here. However this doesn't work well in

...pen (const VixDiskLibConnection connection, + const char *path, + uint32_t flags, + VixDiskLibHandle *handle) +{ + return VIX_OK; +} + +const char * +VixDiskLib_GetTransportMode (VixDiskLibHandle handle) +{ + return "file"; +} + +VixError +VixDiskLib_Close (VixDiskLibHandle handle) +{ + return VIX_OK; +} + +VixError +VixDiskLib_Disconnect (VixDiskLibConnection connection) +{ + return VIX_OK; +} + +VixError +VixDiskLib_GetInfo (VixDiskLibHandle handle, + VixDiskLibInfo **info) +{ + *info = calloc (1, sizeof (struct VixDiskLibInfo...

Probably needs a bit of cleanup, but seems like it is generally the right direction. One thing I've noticed is that the expect test randomly (but rarely) hangs :-( I guess something is racey but I don't know what at the moment. Rich.