Prr tr r - - PowerPoint PPT Presentation
s r s t t t rst Prr tr r s
♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❆✉❣✉st ✷✸✱ ✷✵✶✻ ❙❧✐❞❡ ✶✴✸✶
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✷✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✸✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
✶❚❖♠♦❣r❛♣❤✐❝ ▼✐❝r♦s❝♦♣② ❛♥❞ ❈♦❤❡r❡♥t r❆❞✐♦❧♦❣② ❡①♣❡r✐♠❡♥❚s
❙❧✐❞❡ ✹✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
✶❚❖♠♦❣r❛♣❤✐❝ ▼✐❝r♦s❝♦♣② ❛♥❞ ❈♦❤❡r❡♥t r❆❞✐♦❧♦❣② ❡①♣❡r✐♠❡♥❚s
❙❧✐❞❡ ✹✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✺✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✺✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✻✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✼✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✽✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✾✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✶✵✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
40 50 60 70 80 90 100 110 120 130 1 2 4 8 16 32 Seconds GB written to tape LTFS unmount duration
❙❧✐❞❡ ✶✶✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✶✷✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✶✸✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✶✹✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✶✺✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✶✻✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✶✼✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
✶ // create a communication channel ✷ ch := make(chan *drive) ✸ ✹ // send a "request" to all drives ✺ for _, drv := range drives { ✻ // start a light-weight concurrent process ✼ go func(drv *drive) { ✽ // block until available ✾ drv.acquire() ✶✵ ✶✶ // send the drive on the result channel ✶✷ ch <- drv ✶✸ }(drv) ✶✹ } ✶✺ ✶✻ // receive allocated drive ✶✼ drv := <-ch
❙❧✐❞❡ ✶✽✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
ctx := context.Background() ctx, cancel := WithTimeout(...) ctx, cancel := WithCancel(...) ctx := WithValue(...)
❙❧✐❞❡ ✶✾✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
✶ func reserve(ctx context.Context) (d *drive) { ✷ derived, cancel := context.WithCancel(ctx) ✸ ch := make(chan *drive) ✹ ✺ for _, drv := range drives { ✻ go func(drv *drive) { ✼ if err := drv.acquire(derived); err != nil { ✽ return ✾ } ✶✵ ✶✶ select { ✶✷ case <-derived.Done(): ✶✸ drv.release() ✶✹ return ✶✺ case ch <- drv: ✶✻ } ✶✼ }(drv) ✶✽ } ✶✾ ✷✵ select { ✷✶ case <-ctx.Done: ✷✷ return ✷✸ case d = <-ch: ✷✹ cancel() ✷✺ } ✷✻ ✷✼ return d ✷✽ }
❙❧✐❞❡ ✷✵✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙tr❡❛♠ ❲r✐t❡r ❲r✐t❡r ✭❛✮ t❡r♠✐♥❛t❡ ❉r✐✈❡ ✭❛✮ r❡♣♦rt ❡rr♦r ✭❜✮ r❡q✉❡st ♦t❤❡r ❞r✐✈❡s ✭❜✮ ❝r❡❛t❡ ✭❝✮ ❞r✐✈❡ r❡s♣♦♥s❡ ✭❞✮ ✉♣❞❛t❡ str❡❛♠
❙❧✐❞❡ ✷✶✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙tr❡❛♠ ❲r✐t❡r ❲r✐t❡r ✭❛✮ t❡r♠✐♥❛t❡ ❉r✐✈❡ ✭❛✮ r❡♣♦rt ❡rr♦r ✭❜✮ r❡q✉❡st ♦t❤❡r ❞r✐✈❡s ✭❜✮ ❝r❡❛t❡ ✭❝✮ ❞r✐✈❡ r❡s♣♦♥s❡ ✭❞✮ ✉♣❞❛t❡ str❡❛♠
❙❧✐❞❡ ✷✶✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙tr❡❛♠ ❲r✐t❡r ❲r✐t❡r ✭❛✮ t❡r♠✐♥❛t❡ ❉r✐✈❡ ✭❛✮ r❡♣♦rt ❡rr♦r ✭❜✮ r❡q✉❡st ♦t❤❡r ❞r✐✈❡s ✭❜✮ ❝r❡❛t❡ ✭❝✮ ❞r✐✈❡ r❡s♣♦♥s❡ ✭❞✮ ✉♣❞❛t❡ str❡❛♠
❙❧✐❞❡ ✷✶✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙tr❡❛♠ ❲r✐t❡r ❲r✐t❡r ✭❛✮ t❡r♠✐♥❛t❡ ❉r✐✈❡ ✭❛✮ r❡♣♦rt ❡rr♦r ✭❜✮ r❡q✉❡st ♦t❤❡r ❞r✐✈❡s ✭❜✮ ❝r❡❛t❡ ✭❝✮ ❞r✐✈❡ r❡s♣♦♥s❡ ✭❞✮ ✉♣❞❛t❡ str❡❛♠
❙❧✐❞❡ ✷✶✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✷✷✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✷✸✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✷✹✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
200 400 600 800 1000 1200 1400 1 2 4 8 16 32 64 MB/s Number of concurrent streams of 1 GB Write throughput parallel, chunk ack parallel, no ack single, chunk ack single, no ack
❙❧✐❞❡ ✷✺✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
400 500 600 700 800 900 1000 1100 1200 1300 1 2 4 8 16 32 64 MB/s Number of concurrent streams of 1 GB Write throughput, different chunk sizes 4 MB 32 MB 64 MB 128 MB
❙❧✐❞❡ ✷✻✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✷✼✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✷✼✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
20 40 60 80 100 120 140 160 1 2 4 8 MB/s Number of concurrent write streams of 1 GB Read throughput, 64 MB chunks selective read contiguous read
❙❧✐❞❡ ✷✽✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
2000 4000 6000 8000 10000 12000 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Milliseconds Chunk number Read time per chunk (64 MB)
❙❧✐❞❡ ✷✾✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✸✵✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻
✉ ♥ ✐ ✈ ❡ r s ✐ t ② ♦ ❢ ❝ ♦ ♣ ❡ ♥ ❤ ❛ ❣ ❡ ♥ ♥ ✐ ❡ ❧ s ❜ ♦ ❤ r ✐ ♥ s t ✐ t ✉ t ❡
❙❧✐❞❡ ✸✶✴✸✶ ✖ ❑❧❛✉s ✖ ❍✐❣❤ P❡r❢♦r♠❛♥❝❡ ❚❛♣❡ ❙tr❡❛♠✐♥❣ ✐♥ ❚❛♣r ✖ ❆✉❣✉st ✷✸✱ ✷✵✶✻