libfoedus-core
FOEDUS Core Library
device_emulation_options.cpp
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18 #include "foedus/externalize/externalizable.hpp"
19 #include "foedus/fs/device_emulation_options.hpp"
20 namespace foedus {
21 namespace fs {
22 ErrorStack DeviceEmulationOptions::load(tinyxml2::XMLElement* element) {
23  EXTERNALIZE_LOAD_ELEMENT(element, disable_direct_io_);
24  EXTERNALIZE_LOAD_ELEMENT(element, null_device_);
25  EXTERNALIZE_LOAD_ELEMENT(element, emulated_seek_latency_cycles_);
26  EXTERNALIZE_LOAD_ELEMENT(element, emulated_read_kb_cycles_);
27  EXTERNALIZE_LOAD_ELEMENT(element, emulated_write_kb_cycles_);
28  return kRetOk;
29 }
30 
31 ErrorStack DeviceEmulationOptions::save(tinyxml2::XMLElement* element) const {
32  EXTERNALIZE_SAVE_ELEMENT(element, disable_direct_io_,
33  "Whether to disable Direct I/O and use non-direct I/O instead.");
34  EXTERNALIZE_SAVE_ELEMENT(element, null_device_,
35  "As if we write out to /dev/null. Used to measure performance w/o I/O.");
36  EXTERNALIZE_SAVE_ELEMENT(element, emulated_seek_latency_cycles_,
37  "additional CPU cycles to busy-wait for each seek. 0 (default) disables it.");
38  EXTERNALIZE_SAVE_ELEMENT(element, emulated_read_kb_cycles_,
39  "additional CPU cycles to busy-wait for each 1KB read. 0 (default) disables it."
40  " For example, 4kb read is seek+scan*4 cycles, 1MB read is seek+scan*1000 cycles.");
41  EXTERNALIZE_SAVE_ELEMENT(element, emulated_write_kb_cycles_,
42  "additional CPU cycles to busy-wait for each 1KB write. 0 (default) disables it.");
43  return kRetOk;
44 }
45 
46 } // namespace fs
47 } // namespace foedus
EXTERNALIZE_LOAD_ELEMENT
#define EXTERNALIZE_LOAD_ELEMENT(element, attribute)
Reads a child xml element to load a member variable of this object.
Definition: externalizable.hpp:254
foedus::fs::DeviceEmulationOptions::emulated_seek_latency_cycles_
uint32_t emulated_seek_latency_cycles_
[Experiments] additional CPU cycles to busy-wait for each seek.
Definition: device_emulation_options.hpp:52
foedus
Root package of FOEDUS (Fast Optimistic Engine for Data Unification Services).
Definition: assert_nd.hpp:44
device_emulation_options.hpp
foedus::ErrorStack
Brings error stacktrace information as return value of functions.
Definition: error_stack.hpp:81
foedus::fs::DeviceEmulationOptions::load
ErrorStack load(tinyxml2::XMLElement *element) override
Reads the content of this object from the given XML element.
Definition: device_emulation_options.cpp:22
foedus::fs::DeviceEmulationOptions::emulated_write_kb_cycles_
uint32_t emulated_write_kb_cycles_
[Experiments] additional CPU cycles to busy-wait for each 1KB write.
Definition: device_emulation_options.hpp:63
foedus::kRetOk
const ErrorStack kRetOk
Normal return value for no-error case.
Definition: error_stack.hpp:251
foedus::fs::DeviceEmulationOptions::save
ErrorStack save(tinyxml2::XMLElement *element) const override
Writes the content of this object to the given XML element.
Definition: device_emulation_options.cpp:31
EXTERNALIZE_SAVE_ELEMENT
#define EXTERNALIZE_SAVE_ELEMENT(element, attribute, comment)
Adds an xml element to represent a member variable of this object.
Definition: externalizable.hpp:234
foedus::fs::DeviceEmulationOptions::null_device_
bool null_device_
[Experiments] as if we write out to /dev/null.
Definition: device_emulation_options.hpp:49
foedus::fs::DeviceEmulationOptions::emulated_read_kb_cycles_
uint32_t emulated_read_kb_cycles_
[Experiments] additional CPU cycles to busy-wait for each 1KB read.
Definition: device_emulation_options.hpp:58
foedus::fs::DeviceEmulationOptions::disable_direct_io_
bool disable_direct_io_
[Experiments] Whether to disable Direct I/O and use non-direct I/O instead.
Definition: device_emulation_options.hpp:46