performance measurement and tuning of remote … · performance measurement and tuning of remote...
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Performance measurement and tuning of remoteacquisition
Lukasz Makowski
February 2, 2016
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Location
Netherlands Forensic InstituteSupervisor : Ruud Schramp
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Agenda
1 Remote acquisition - research motivation introduction
2 Research scope and questions posed
3 Approach & methods taken
4 Results
5 Future work
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Forensic acquisition
”Old-school” approach:
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Forensic acquisition
”Old-school” approach:
![Page 6: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/6.jpg)
Forensic acquisition
![Page 7: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/7.jpg)
Forensic acquisition
The bottlenecks in the current process:
quantity : regular disk size increases
![Page 8: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/8.jpg)
Forensic acquisition
The bottlenecks in the current process:
quantity : regular disk size increases
![Page 9: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/9.jpg)
Forensic acquisition
Data source : http://www.mkomo.com/cost-per-gigabyte
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Forensic acquisition
The bottlenecks in the current process:
quantity : regular disk size increases
staffing : forensic experts cannot be easily multiplied :(
legal : court approval takes time
But there is a possible solution! (at least to the first two points. . . )
![Page 11: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/11.jpg)
Forensic acquisition
The bottlenecks in the current process:
quantity : regular disk size increases
staffing : forensic experts cannot be easily multiplied :(
legal : court approval takes time
But there is a possible solution! (at least to the first two points. . . )
![Page 12: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/12.jpg)
Forensic acquisition
The bottlenecks in the current process:
quantity : regular disk size increases
staffing : forensic experts cannot be easily multiplied :(
legal : court approval takes time
But there is a possible solution! (at least to the first two points. . . )
![Page 13: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/13.jpg)
Forensic acquisition
The bottlenecks in the current process:
quantity : regular disk size increases
staffing : forensic experts cannot be easily multiplied :(
legal : court approval takes time
But there is a possible solution! (at least to the first two points. . . )
![Page 14: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/14.jpg)
Forensic triage - the cure for pain?
Triage is the process ofdetermining the priorityof patients’ treatmentsbased on the severity oftheir condition. Thisrations patienttreatment efficientlywhen resources areinsufficient for all to betreated immediately.
Source : https://en.wikipedia.org/wiki/TriageSource : https://cartadvocate.files.wordpress.com/2015/03/img 3788.jpg
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Forensic triage - the cure for pain?
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Forensic triage - the cure for pain?
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Remote triage
Remote triage - problem:
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Remote triage
Remote triage - approach:
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Remote triage
Remote triage’ issues:
WAN links introduce whole subset of problems (delay,bandwidth, packet loss, . . . )
iSCSI uses TCP in transport layer (TCP limitations inherited)
iSCSI is not well suited to WAN links
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Remote triage
Remote triage’ issues:
WAN links introduce whole subset of problems (delay,bandwidth, packet loss, . . . )
iSCSI uses TCP in transport layer (TCP limitations inherited)
iSCSI is not well suited to WAN links
![Page 21: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/21.jpg)
Remote triage
Remote triage’ issues:
WAN links introduce whole subset of problems (delay,bandwidth, packet loss, . . . )
iSCSI uses TCP in transport layer (TCP limitations inherited)
iSCSI is not well suited to WAN links
![Page 22: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/22.jpg)
Remote triage
Remote triage’ issues:
WAN links introduce whole subset of problems (delay,bandwidth, packet loss, . . . )
iSCSI uses TCP in transport layer (TCP limitations inherited)
iSCSI is not well suited to WAN links
![Page 23: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/23.jpg)
Remote triage - issues
Essentially the problem can be synthesized to simple question :
How to make the remote triage as efficient as possible?
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Remote triage - issues
Essentially the problem can be synthesized to simple question :How to make the remote triage as efficient as possible?
![Page 25: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/25.jpg)
Remote triage - issues
Areas where the speed-up can be potentially achieved:
TCP protocol tuning
iSCSI stack tuning
Acquisition I/O optimisation
Yes. . . TCP and iSCSI options left in the defaults
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Remote triage - issues
Areas where the speed-up can be potentially achieved:
TCP protocol tuning
iSCSI stack tuning
Acquisition I/O optimisation
Yes. . . TCP and iSCSI options left in the defaults
![Page 27: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/27.jpg)
Remote triage - issues
Areas where the speed-up can be potentially achieved:
TCP protocol tuning
iSCSI stack tuning
Acquisition I/O optimisation
Yes. . . TCP and iSCSI options left in the defaults
![Page 28: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/28.jpg)
Remote triage - issues
Areas where the speed-up can be potentially achieved:
TCP protocol tuning
iSCSI stack tuning
Acquisition I/O optimisation
Yes. . . TCP and iSCSI options left in the defaults
![Page 29: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/29.jpg)
Remote triage - issues
Areas where the speed-up can be potentially achieved:
TCP protocol tuning
iSCSI stack tuning
Acquisition I/O optimisation
Yes. . . TCP and iSCSI options left in the defaults
![Page 30: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/30.jpg)
Research scope
Acquisition I/O optimisation :
Is it feasible to enhance a transfer rate for acquisitionperformed on the iSCSI block device?
Which techniques an application can use to improve on thetransmission rate?
How a link delay influences the experiment?
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Research scope
Acquisition I/O optimisation :
Is it feasible to enhance a transfer rate for acquisitionperformed on the iSCSI block device?
Which techniques an application can use to improve on thetransmission rate?
How a link delay influences the experiment?
![Page 32: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/32.jpg)
Research scope
Acquisition I/O optimisation :
Is it feasible to enhance a transfer rate for acquisitionperformed on the iSCSI block device?
Which techniques an application can use to improve on thetransmission rate?
How a link delay influences the experiment?
![Page 33: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/33.jpg)
Research scope
Acquisition I/O optimisation :
Is it feasible to enhance a transfer rate for acquisitionperformed on the iSCSI block device?
Which techniques an application can use to improve on thetransmission rate?
How a link delay influences the experiment?
![Page 34: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/34.jpg)
Research scope
Researching on potential I/O optimisation methods:
prefetching (implies the usage of cache)
read-aheadread-behind
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Research scope
Researching on potential I/O optimisation methods:
prefetching (implies the usage of cache)
read-aheadread-behind
![Page 36: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/36.jpg)
Research scope
Researching on potential I/O optimisation methods:
prefetching (implies the usage of cache)
read-ahead
read-behind
![Page 37: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/37.jpg)
Research scope
Researching on potential I/O optimisation methods:
prefetching (implies the usage of cache)
read-aheadread-behind
![Page 38: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/38.jpg)
Research scope - prefetching
Read-ahead : read block-size → cache MISS → readblock-size+read-ahead
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Research scope - prefetching
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Research scope - prefetching
Read-ahead : read block-size → cache HIT
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Research scope
Researching on potential I/O optimisation methods:
prefetching (implies the usage of cache)
read-aheadread-behind
parallelism
![Page 42: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/42.jpg)
Research scope
Researching on potential I/O optimisation methods:
prefetching (implies the usage of cache)
read-aheadread-behind
parallelism
![Page 43: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/43.jpg)
Research scope - parallelism
Single process, waiting for the reply
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Research scope - parallelism
More processes, an attempt to utilise the wait time
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Research scope - parallelism
Source : http://www.potaroo.net/ispcol/2005-06/fig4.jpg
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Methods - creating triage.py
Goals:
Repeatable triage process (tests)
Two modes : sequential & parallel
Adjustable parallel workers number
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Methods - creating triage.py
Goals:
Repeatable triage process (tests)
Two modes : sequential & parallel
Adjustable parallel workers number
![Page 48: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/48.jpg)
Methods - creating triage.py
Goals:
Repeatable triage process (tests)
Two modes : sequential & parallel
Adjustable parallel workers number
![Page 49: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/49.jpg)
Methods - creating triage.py
Goals:
Repeatable triage process (tests)
Two modes : sequential & parallel
Adjustable parallel workers number
![Page 50: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/50.jpg)
Methods - creating triage.py
Solution:
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Methods - parallelism
Multiprocessing. Making The SleuthKit (TSK) parallel.
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Methods - prefetching
Cache implementation : Fusecoraw1
1https://homepages.staff.os3.nl/˜delaat/rp/2013-2014/p71/report.pdf
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Methods - prefetching
Expanding fusecoraw with read-ahead, read-behind functionality.Simplified approach.
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Methods - prefetchingReads issued to the FUSE filesystem are being extended by theadditional read().
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Methods - prefetching
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Methods - Lab setup
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Methods - Lab setup
Constant delay applied : 0, 10, 20 [ms]
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Experiments performed
relativedelay (ms)
test performedprefetching parallelism repetitions
0 X X 3
10 X X 3
20 X X 3
Table : Test sets summary
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Experiments performed
Chosen metrics:
Average throughput (tcpdump + tcptrace)
Elapsed time (GNU time)
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Experiments performed
Prefetching
readahead
readbehind
0 8192 65536
0 X X X
8192 X X -
65536 X - X
Table : Chosen read-ahead and read-behind values
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Results
Prefetching (Read-ahead & read-behind)
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Results
Prefetching (Read-ahead & read-behind)
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Results
Prefetching tests observations
Average throughput may indicate the triage process speed-up,but . . .
It’s better to look at the execution time
When no delay was introduced; read-ahead of 8KiB, had thesmallest mean execution time
With the delay; I/O without prefetching had the smallest timemetric
![Page 64: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/64.jpg)
Results
Prefetching tests observations
Average throughput may indicate the triage process speed-up,but . . .
It’s better to look at the execution time
When no delay was introduced; read-ahead of 8KiB, had thesmallest mean execution time
With the delay; I/O without prefetching had the smallest timemetric
![Page 65: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/65.jpg)
Results
Prefetching tests observations
Average throughput may indicate the triage process speed-up,but . . .
It’s better to look at the execution time
When no delay was introduced; read-ahead of 8KiB, had thesmallest mean execution time
With the delay; I/O without prefetching had the smallest timemetric
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Results
Prefetching tests observations
Average throughput may indicate the triage process speed-up,but . . .
It’s better to look at the execution time
When no delay was introduced; read-ahead of 8KiB, had thesmallest mean execution time
With the delay; I/O without prefetching had the smallest timemetric
![Page 67: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/67.jpg)
Results
Prefetching tests observations
Average throughput may indicate the triage process speed-up,but . . .
It’s better to look at the execution time
When no delay was introduced; read-ahead of 8KiB, had thesmallest mean execution time
With the delay; I/O without prefetching had the smallest timemetric
![Page 68: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/68.jpg)
Experiments performed
Parallelism
directoryscanner
filefetcher
1 2 4
1 X - -
2 - X -
4 - - X
Table : triage.py workers setup
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Results
Parallelism
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Results
Parallelism
![Page 71: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/71.jpg)
Results
Parallelism test observations
Elapsed time barchart suggests that 8 workers performsurprisingly well for the delayed link
However, the throughput chart does not record expectedspeed-up (the differences are small)
Probably the external factor which influenced the testoccurred (caching?)
![Page 72: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/72.jpg)
Results
Parallelism test observations
Elapsed time barchart suggests that 8 workers performsurprisingly well for the delayed link
However, the throughput chart does not record expectedspeed-up (the differences are small)
Probably the external factor which influenced the testoccurred (caching?)
![Page 73: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/73.jpg)
Results
Parallelism test observations
Elapsed time barchart suggests that 8 workers performsurprisingly well for the delayed link
However, the throughput chart does not record expectedspeed-up (the differences are small)
Probably the external factor which influenced the testoccurred (caching?)
![Page 74: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/74.jpg)
Results
Parallelism test observations
Elapsed time barchart suggests that 8 workers performsurprisingly well for the delayed link
However, the throughput chart does not record expectedspeed-up (the differences are small)
Probably the external factor which influenced the testoccurred (caching?)
![Page 75: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/75.jpg)
Lessons learnt
OS tries to be your best friend. It optimises/caches wheneverit can. Not necessarily bad, but it has to be understood whiledesigning the tests.
Trying to abstract the research from the components it willeventually need to rely on, is close to agreeing that its resultsmay become ”abstract”.
![Page 76: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/76.jpg)
Lessons learnt
OS tries to be your best friend. It optimises/caches wheneverit can. Not necessarily bad, but it has to be understood whiledesigning the tests.
Trying to abstract the research from the components it willeventually need to rely on, is close to agreeing that its resultsmay become ”abstract”.
![Page 77: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/77.jpg)
Lessons learnt
OS tries to be your best friend. It optimises/caches wheneverit can. Not necessarily bad, but it has to be understood whiledesigning the tests.
Trying to abstract the research from the components it willeventually need to rely on, is close to agreeing that its resultsmay become ”abstract”.
![Page 78: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/78.jpg)
Future work
Follow up on the I/O optimisation techniques (extendpresented tests)
Try to reuse tuning knowledge from the papers whichinvestigated iSCSI sequential writes over the delayed links
Assess chosen iSCSI implementation against Analysis of iSCSIShort Blocks Access paper criteria
Is getting the work done without TCP possible? ExploringATA over Ethernet (AoE) feasibility for the remote acquisition
![Page 79: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/79.jpg)
Future work
Follow up on the I/O optimisation techniques (extendpresented tests)
Try to reuse tuning knowledge from the papers whichinvestigated iSCSI sequential writes over the delayed links
Assess chosen iSCSI implementation against Analysis of iSCSIShort Blocks Access paper criteria
Is getting the work done without TCP possible? ExploringATA over Ethernet (AoE) feasibility for the remote acquisition
![Page 80: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/80.jpg)
Future work
Follow up on the I/O optimisation techniques (extendpresented tests)
Try to reuse tuning knowledge from the papers whichinvestigated iSCSI sequential writes over the delayed links
Assess chosen iSCSI implementation against Analysis of iSCSIShort Blocks Access paper criteria
Is getting the work done without TCP possible? ExploringATA over Ethernet (AoE) feasibility for the remote acquisition
![Page 81: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/81.jpg)
Future work
Follow up on the I/O optimisation techniques (extendpresented tests)
Try to reuse tuning knowledge from the papers whichinvestigated iSCSI sequential writes over the delayed links
Assess chosen iSCSI implementation against Analysis of iSCSIShort Blocks Access paper criteria
Is getting the work done without TCP possible? ExploringATA over Ethernet (AoE) feasibility for the remote acquisition
![Page 82: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/82.jpg)
Future work
Follow up on the I/O optimisation techniques (extendpresented tests)
Try to reuse tuning knowledge from the papers whichinvestigated iSCSI sequential writes over the delayed links
Assess chosen iSCSI implementation against Analysis of iSCSIShort Blocks Access paper criteria
Is getting the work done without TCP possible? ExploringATA over Ethernet (AoE) feasibility for the remote acquisition
![Page 83: Performance measurement and tuning of remote … · Performance measurement and tuning of remote acquisition ... WAN links introduce whole subset of problems ... Researching on potential](https://reader031.vdocuments.mx/reader031/viewer/2022022018/5b8baa0209d3f21d638bcb40/html5/thumbnails/83.jpg)
Q&A
Questions?