# Volunteer Down: How COVID-19 Created the Largest Idling Supercomputer on Earth
## 5 Critical Discussion and Related Work  
The proposed approach targets mainly volunteer grid computing projects and, in particular, the mentioned shortcomings of cross-project resource sharing. The main intention is to improve resource sharing across VC projects and to set up VC projects more easily making use of established and well-accepted cloud-native technologies. Therefore, it shares similar limitations like every other volunteer grid computing project. Thus, the architecture supports embarrassingly parallel tasks that need no or little communication among the tasks [5]. If this is not the case, volunteer parallel computing projects or even HPC supercomputing might be a better fit. However, this paper does not focus on this kind of parallel VC or even HPC. The paper does not even claim to have or provide answers of value for these parallel computing or HPC supercomputing domains. Furthermore, the proposed approach follows conceptually a middleware-based path and shares, therefore, comparable limitations to the BOINC-approach [13; 73]. To reach project awareness and enable necessary trust are complex tasks in themselves, even in a single-research VC project. Single-research projects might even have advantages here because contributors do not need any complex overview of various research or other projects. However, this aspect is getting more complicated for a middleware-based approach [74]. The contributors need project awareness, and some project prioritization means. Some contributors want to support disease-related projects but might be not interested in supporting prime-number mathematical research. In the case of BOINC, a kind of trusted community already exists, and all BOINC-based projects have passed a kind of quality gate, and all BOINC-based projects are research-focused. This gatekeeper role of BOINC makes it easier for BOINC contributors to establish trust. However, projects that are not aware of the gatekeeper are not aware to contributors as well. Thus, multi-project gatekeeping in VC always has a kind of censorship. Therefore, the proposed approach enables intentionally to set up VC infrastructures that could process arbitrary computations--for instance, doing mundane crypto-mining for purely monetary reasons. We do not think that crypto-mining (or other doubtable motivations) would be a useful and ethical form of VC. However, this should not be the decision of a non-democratic legitimized gatekeeping institution but the personal choice of every single VC contributor according to their own criteria [75; 76]. Therefore, this proposal intentionally does not assume a well-trusted gatekeeper that filters qualified from non-qualified projects. However, this missing gatekeeping role makes it more complicated for contributors to select VC projects that are worth being supported. The reader should take additional surveys on VC, like [5; 64] or cloud computing [2; 3; 67; 69; 70], into account to derive their own conclusions and discuss this perspective paper critically. For instance, Ref. [5] provides a broad and excellent overview of several grid-based, cloud-based, mobile, and parallel VC projects, frameworks, and technological approaches. As the reader may have noticed, this perspective paper is highly influenced by [5]. However, to the best of the author's knowledge, there does not exist any survey that covers cloud computing and VC in parallel focusing particularly on the aspect of how to combine concepts of both domains to overcome the project exclusiveness problem in VC. It is interesting to see that grid- and cloud-based projects form the majority of VC projects (see Figure 4). Thus, there is some kind of attraction in adopting Cloud technologies for VC (see Figure 5). In particular, recent cloud-native trends like standardization of fine-grained deployment units via containers provide exciting opportunities. _\"The efficient use of available resources and tight integration with the host operating system makes container technologies a plausible choice for VC.