# Difference between revisions of "Risk analysis"

From Superoptimization

m (→Risk register) |
(Final risks) |
||

Line 1: | Line 1: | ||

− | For each risk we | + | For each risk we gave the probability of it occurring (1-10) and the impact (1-3, with 1 being minor, and 3 being project killer). A mitigation was provided for any risk with an impact of 3, or where the product of likelihood and impact was greater than 10. |

+ | |||

+ | With the project complete, all risks have a likelihood of zero. The list is retained for reference in future projects. To see how values changed over the project, use the Wiki history. | ||

== Risk register == | == Risk register == | ||

Line 8: | Line 10: | ||

|- | |- | ||

| Hard limit to search space prevents useful optimization | | Hard limit to search space prevents useful optimization | ||

− | | | + | | 0 || 3 || 0 |

| New risk identified for interim report. It seems you can either superoptimize an entire instruction set for very short sequences of code, or much longer code sequences, but only for a small subset of the entire instruction set. Mitigation is to identify heuristics: 1) to guide through the search space; and 2) to reduce the size of the search space. | | New risk identified for interim report. It seems you can either superoptimize an entire instruction set for very short sequences of code, or much longer code sequences, but only for a small subset of the entire instruction set. Mitigation is to identify heuristics: 1) to guide through the search space; and 2) to reduce the size of the search space. | ||

|- | |- | ||

| Computational demand is too high. | | Computational demand is too high. | ||

− | | | + | | 0 || 3 || 0 |

| Focus on optimal algorithms. Ensure adequate compute power. Likelihood reduced for interim report, since we have established that there are superoptimization strategies that are feasible with current computing power (see initial results for [[Work Package 3|work package 3]]). | | Focus on optimal algorithms. Ensure adequate compute power. Likelihood reduced for interim report, since we have established that there are superoptimization strategies that are feasible with current computing power (see initial results for [[Work Package 3|work package 3]]). | ||

|- | |- | ||

| Some features of modern processors cannot be superoptimized. | | Some features of modern processors cannot be superoptimized. | ||

− | | | + | | 0 || 2 || 0 |

| Attempt to identify ways of applying to these features. Likelihood reduced for interim report, since we have identified sufficient features to make superoptimization attractive (see [[Work Package 1|work package 1]]). | | Attempt to identify ways of applying to these features. Likelihood reduced for interim report, since we have identified sufficient features to make superoptimization attractive (see [[Work Package 1|work package 1]]). | ||

|- | |- | ||

| Project is too complex for 4 months. | | Project is too complex for 4 months. | ||

− | | | + | | 0 || 2 || 0 |

| Tight project management (weekly meetings). Likelihood reduced for interim report, since we have established all the main criteria, and believe we will finish without difficulty. | | Tight project management (weekly meetings). Likelihood reduced for interim report, since we have established all the main criteria, and believe we will finish without difficulty. | ||

|} | |} |

## Latest revision as of 15:04, 20 October 2014

For each risk we gave the probability of it occurring (1-10) and the impact (1-3, with 1 being minor, and 3 being project killer). A mitigation was provided for any risk with an impact of 3, or where the product of likelihood and impact was greater than 10.

With the project complete, all risks have a likelihood of zero. The list is retained for reference in future projects. To see how values changed over the project, use the Wiki history.

## Risk register

Description | Likelihood | Impact | Risk | Mitigation |
---|---|---|---|---|

Hard limit to search space prevents useful optimization | 0 | 3 | 0 | New risk identified for interim report. It seems you can either superoptimize an entire instruction set for very short sequences of code, or much longer code sequences, but only for a small subset of the entire instruction set. Mitigation is to identify heuristics: 1) to guide through the search space; and 2) to reduce the size of the search space. |

Computational demand is too high. | 0 | 3 | 0 | Focus on optimal algorithms. Ensure adequate compute power. Likelihood reduced for interim report, since we have established that there are superoptimization strategies that are feasible with current computing power (see initial results for work package 3). |

Some features of modern processors cannot be superoptimized. | 0 | 2 | 0 | Attempt to identify ways of applying to these features. Likelihood reduced for interim report, since we have identified sufficient features to make superoptimization attractive (see work package 1). |

Project is too complex for 4 months. | 0 | 2 | 0 | Tight project management (weekly meetings). Likelihood reduced for interim report, since we have established all the main criteria, and believe we will finish without difficulty. |