Visit Our UNIX and Linux User Community

Linux and UNIX Man Pages

Test Your Knowledge in Computers #124
Difficulty: Easy
Generally speaking, Linux is only a Kernel, while Linux distributions are treated as an OS.
True or False?
Linux & Unix Commands - Search Man Pages

dat_srq_resize(3dat) [sunos man page]

dat_srq_resize(3DAT)				     Direct Access Transport Library Functions				      dat_srq_resize(3DAT)

NAME
dat_srq_resize - modify the size of the shared receive queue SYNOPSIS
cc [ flag... ] file... -ldat [ library... ] #include <dat/udat.h> DAT_RETURN dat_srq_resize ( IN DAT_SRQ_HANDLE srq_handle, IN DAT_COUNT srq_max_recv_dto ) PARAMETERS
srq_handle A handle for an instance of the SRQ. srq_max_recv_dtoThe new maximum number of Recv DTOs that Shared Receive Queue must hold. DESCRIPTION
The dat_srq_resize() function modifies the size of the queue of SRQ. Resizing of Shared Receive Queue should not cause any incoming messages on any of the EPs that use the SRQ to be lost. If the number of outstanding Recv buffers on the SRQ is larger then the requested srq_max_recv_dto, the operation returns DAT_INVALID_STATE and do not change SRQ. This includes not just the buffers on the SRQ but all outstanding Receive buffers that had been posted to the SRQ and whose completions have not reaped yet. Thus, the outstanding buffers include the buffers on SRQ, the buffers posted to SRQ at are at SRQ associ- ated EPs, and the buffers posted to SRQ for which completions have been generated but not yet reaped by Consumer from recv_evds of the EPs that use the SRQ. If the requested srq_max_recv_dto is below the SRQ low watermark, the operation returns DAT_INVALID_STATE and does not change SRQ. RETURN VALUES
DAT_SUCCESS The operation was successful. DAT_INVALID_HANDLE The srq_handle argument is an invalid DAT handle. DAT_INVALID_PARAMETER The srq_max_recv_dto argument is invalid. DAT_INSUFFICIENT_RESOURCES The operation failed due to resource limitations. DAT_INVALID_STATE Invalid state. Either the number of entries on the SRQ exceeds the requested SRQ queue length or the requested SRQ queue length is smaller than the SRQ low watermark. USAGE
The dat_srq_resize() function is required not to lose any buffers. Thus, it cannot shrink below the outstanding number of Recv buffers on SRQ. There is no requirement to shrink the SRQ to return DAT_SUCCESS. The quality of the implementation determines how closely to the Consumer-requested value the Provider shrinks the SRQ. For example, the Provider can shrink the SRQ to the Consumer-requested value and if the requested value is smaller than the outstanding buffers on SRQ, return DAT_INVALID_STATE; or the Provider can shrink to some value larger than that requested by the Consumer but below current SRQ size; or the Provider does not change the SRQ size and still returns DAT_SUCCESS. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard: uDAPL, 1.2 | +-----------------------------+-----------------------------+ |MT-Level |Unsafe | +-----------------------------+-----------------------------+ SEE ALSO
dat_srq_create(3DAT), dat_srq_free(3DAT), dat_srq_post_recv(3DAT), dat_srq_query(3DAT), dat_srq_set_lw(3DAT), libdat(3LIB), attributes(5) SunOS 5.10 16 Jul 2004 dat_srq_resize(3DAT)

Check Out this Related Man Page

dat_srq_create(3DAT)				     Direct Access Transport Library Functions				      dat_srq_create(3DAT)

NAME
dat_srq_create - create an instance of a shared receive queue SYNOPSIS
cc [ flag... ] file... -ldat [ library... ] #include <dat/udat.h> DAT_RETURN dat_srq_create ( IN DAT_IA_HANDLE ia_handle, IN DAT_PZ_HANDLE pz_handle, IN DAT_SRQ_ATTR *srq_attr, OUT DAT_SRQ_HANDLE *srq_handle ) PARAMETERS
ia_handle A handle for an open instance of the IA to which the created SRQ belongs. pz_handle A handle for an instance of the Protection Zone. srq_attr A pointer to a structure that contains Consumer-requested SRQ attributes. srq_handle A handle for the created instance of a Shared Receive Queue. DESCRIPTION
The dat_srq_create() function creates an instance of a Shared Receive Queue (SRQ) that is provided to the Consumer as srq_handle. If the value of DAT_RETURN is not DAT_SUCCESS, the value of srq_handle is not defined. The created SRQ is unattached to any Endpoints. The Protection Zone pz_handle allows Consumers to control what local memory can be used for the Recv DTO buffers posted to the SRQ. Only memory referred to by LMRs of the posted Recv buffers that match the SRQ Protection Zone can be accessed by the SRQ. The srq_attributes argument specifies the initial attributes of the created SRQ. If the operation is successful, the created SRQ will have the queue size at least max_recv_dtos and the number of entries on the posted Recv scatter list of at lease max_recv_iov. The created SRQ can have the queue size and support number of entries on post Recv buffers larger than requested. Consumer can query SRQ to find out the actual supported queue size and maximum Recv IOV. The Consumer must set low_watermark to DAT_SRQ_LW_DEFAULT to ensure that an asynchronous event will not be generated immediately, since there are no buffers in the created SRQ. The Consumer should set the Maximum Receive DTO attribute and the Maximum number of elements in IOV for posted buffers as needed. When an associated EP tries to get a buffer from SRQ and there are no buffers available, the behavior of the EP is the same as when there are no buffers on the EP Recv Work Queue. RETURN VALUES
DAT_SUCCESS The operation was successful. DAT_INSUFFICIENT_RESOURCES The operation failed due to resource limitations. DAT_INVALID_HANDLE Either ia_handle or pz_handle is an invalid DAT handle. DAT_INVALID_PARAMETER One of the parameters is invalid. Either one of the requested SRQ attributes was invalid or a combination of attributes is invalid. DAT_MODEL_NOT_SUPPORTED The requested Model was not supported by the Provider. USAGE
SRQ is created by the Consumer prior to creation of the EPs that will be using it. Some Providers might restrict whether multiple EPs that share a SRQ can have different Protection Zones. Check the srq_ep_pz_difference_support Provider attribute. The EPs that use SRQ might or might not use the same recv_evd. Since a Recv buffer of SRQ can be used by any EP that is using SRQ, the Consumer should ensure that the posted Recv buffers are large enough to receive an incoming message on any of the EPs. If Consumers do not want to receive an asynchronous event when the number of buffers in SRQ falls below the Low Watermark, they should leave its value as DAT_SRQ_LW_DEFAULT. If Consumers do want to receive a notification, they can set the value to the desired one by calling dat_srq_set_lw(3DAT). SRQ allows the Consumer to use fewer Recv buffers then posting the maximum number of buffers for each connection. If the Consumer can upper bound the number of incoming messages over all connections whose local EP is using SRQ, then instead of posting this maximum for each con- nection the Consumer can post them for all connections on SRQ. For example, the maximum utilized link bandwidth divided over the message size can be used for an upper bound. Depending on the underlying Transport, one or more messages can arrive simultaneously on an EP that is using SRQ. Thus, the same EP can have multiple Recv buffers in its possession without these buffers being on SRQ or recv_evd. Since Recv buffers can be used by multiple connections of the local EPs that are using SRQ, the completion order of the Recv buffers is no longer guaranteed even when they use of the same recv_evd. For each connection the Recv buffers completion order is guaranteed to be in the order of the posted matching Sends to the other end of the connection. There is no ordering guarantee that Receive buffers will be returned in the order they were posted even if there is only a single connection (Endpoint) associated with the SRQ. There is no ordering guarantee between different connections or between different recv_evds. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard: uDAPL, 1.2 | +-----------------------------+-----------------------------+ |MT-Level |Safe | +-----------------------------+-----------------------------+ SEE ALSO
dat_srq_free(3DAT), dat_srq_post_recv(3DAT), dat_srq_query(3DAT), dat_srq_resize(3DAT), dat_srq_set_lw(3DAT), libdat(3LIB), attributes(5) SunOS 5.11 11 Sep 2006 dat_srq_create(3DAT)

Featured Tech Videos