ShareJIT: JIT Code Cache Sharing across Processes and Its Practical Implementation

Just-in-time (JIT) compilation coupled with code caching are widely used to improve performance in dynamic programming language implementations. These code caches, along with the associated profiling data for the hot code, however, consume significant amounts of memory. Furthermore, they incur extra JIT compilation time for their creation. On Android, the current standard JIT compiler and its code caches are not shared among processes---that is, the runtime system maintains a private code cache, and its associated data, for each runtime process. However, applications running on the same platform tend to share multiple libraries in common. Sharing cached code across multiple applications and multiple processes can lead to a reduction in memory use. It can directly reduce compile time. It can also reduce the cumulative amount of time spent interpreting code. All three of these effects can improve actual runtime performance. In this paper, we describe ShareJIT, a global code cache for JITs that can share code across multiple applications and multiple processes. We implemented ShareJIT in the context of the Android Runtime (ART), a widely used, state-of-the-art system. To increase sharing, our implementation constrains the amount of context that the JIT compiler can use to optimize the code. This exposes a fundamental tradeoff: increased specialization to a single process' context decreases the extent to which the compiled code can be shared. In ShareJIT, we limit some optimization to increase shareability. To evaluate the ShareJIT, we tested 8 popular Android apps in a total of 30 experiments. ShareJIT improved overall performance by 9% on average, while decreasing memory consumption by 16% on average and JIT compilation time by 37% on average.Comment: OOPSLA 201

Frequency steps and compositions determine properties of needling sensation during electroacupuncture

AbstractObjectiveTo investigate the relationship of electro-parameters and the electroacupuncture sensation (EAS), which is thought to be an important factor for optimal treatment.MethodsThe frequency steps and compositions of three frequently used electrical stimulations were set when the switch of the electroacupuncture apparatus was turned to the second or third grade of the dense-disperse frequency wave (DD2 and DD3, respectively) or the second grade of the continuous wave (C2). Three groups of patients according to the three electroacupuncture stimulations were divided again into three sub-groups according to the stimulated acupoints: the face acupoint Quanliao (SI 18), the upper-limb acupoint Quchi (LI 11) and the back acupoint Dachangshu (BL 25). The EAS values were measured every 5 min during 30 min electroacupuncture treatments using a visual analogue scale.ResultsThe frequency compositions of the three electroacupuncture stimulations were 3.3 and 33 Hz, 12.5 and 66.7 Hz, and 3.3 and 3.3 Hz; each frequency step was 30, 54 and 0 Hz, respectively. In each sub-group of the C2 group, the EAS values from 10 to 30 min were significantly weaker than at 0 min. The sensation fluctuations in the DD2 and DD3 groups were different during the 30 min.ConclusionThe greater the frequency step of the electroacupuncture stimulation, the longer the needling sensation lasted. The electroacupuncture stimulations of the DD3 group were unsuitable for the facial acupoint because of its painful and uncomfortable EAS, but more suitable for the back acupoint

Post-seismic relaxation during 2015 to 2020 for the large East Asia earthquakes

During the last 120 years, several large (M>7.5) continental earthquakes (Fig. 1), such as the 1905 Tsetserleg (Mw 7.9)-Bolnay (Mw 8.3) earthquakes and 1957 Mw 8.1 Bogd earthquake, occurred in the East Asia where several important active fault zones exist (e.g. Tibetan Plateau region). Large earthquakes induce a stress change in the ductile lower crust and upper mantle which is relaxed viscoelastically in the years to decades following these events. The viscoelastic relaxation process offers a good opportunity to investigate the rheological structure of the lithosphere. What's more, apparent viscosities are often seen to increase with time since the earthquake. Thus, exploring the viscosities from the 2015 to 2020 post-seismic deformation and combining them with previous studies help us construct the evolution of the regional rheology. Here, we use Sentinel-1 data acquired over ascending and descending orbits during the years 2015-2020 to study the post-seismic deformation for the Bogd earthquake, the Tsetserleg-Bolnay earthquakes and other big (M>7.5) East Asia earthquakes, and explore the lithospheric rheology of these regions. Now, we obtained the LOS displacements from ascending and descending orbits for the Bogd earthquake (Fig. 2a), Tsetserleg-Bolnay earthquakes (Fig. 2b), Manyi earthquake (Fig. 2c) and Balochistan earthquake (Fig. 2d). For the Bogd earthquake, the descending data shows a lobe of up to 1 cm of LOS decrease at the south of the fault. For the Tsetserleg-Bolnay earthquakes, there is a lobe of up to 4 cm of LOS decrease at the southwest of Bolnay fault and the north of fault shows a up to 8 cm of LOS increase. The ascending data for the Manyi earthquake shows an opposite LOS displacement at the both sides of the fault, but there is no significant post-seismic signal for the descending data. For the Balochistan earthquake, the ascending data shows lobes of both LOS increase and decrease (up to 15 cm) and the descending data shows a lobe of up to 10 cm of LOS decrease. Next, we will obtain the post-seismic deformation for other earthquakes (Fig. 1). Then the forward simulations of post-seismic displacements will be generated using RELAX software. Finally, the optimal viscosity values that best fit the observation data from 2015 to 2020 will be solved using a grid search approach among various forward simulations

Rheology of the Zagros Lithosphere from PostSeismic Deformation of the 2017 Mw7.3 Kermanshah, Iraq, Earthquake

We use 2018–2020 Sentinel1 InSAR time series data to study postseismic deformation processes following the 2017 Mw 7.3 Kermanshah, Iraq earthquake. We remove displacements caused by two large aftershock sequences from the displacement field. We find that for a six month period the response is dominated by afterslip along the updip extension of the coseismic rupture zone, producing up to 6 cm of radar lineofsight displacements. The moment magnitude of afterslip is Mw 5.9 or 12% of the mainshock moment. After that period, the displacement field is best explained by viscoelastic relaxation and a lower crustal viscosity of ηlc=1-0.4+0.8×1019Pas. The viscosity of the uppermost mantle is not constrained by the data, except that it is larger than 0.6×1019Pas. The relatively high lower crustal and uppermost mantle viscosities are consistent with a cold and dry lithosphere of the Zagros region

Rheology of the Zagros Lithosphere from Post-Seismic Deformation of the 2017 Mw7.3 Kermanshah, Iraq, Earthquake

We use 2018–2020 Sentinel-1 InSAR time series data to study post-seismic deformation processes following the 2017 Mw 7.3 Kermanshah, Iraq earthquake. We remove displacements caused by two large aftershock sequences from the displacement field. We find that for a six month period the response is dominated by afterslip along the up-dip extension of the coseismic rupture zone, producing up to 6 cm of radar line-of-sight displacements. The moment magnitude of afterslip is Mw 5.9 or 12% of the mainshock moment. After that period, the displacement field is best explained by viscoelastic relaxation and a lower crustal viscosity of η l c = 1 − 0.4 + 0.8 × 10 19   Pas . The viscosity of the uppermost mantle is not constrained by the data, except that it is larger than 0.6 × 10 19   Pas . The relatively high lower crustal and uppermost mantle viscosities are consistent with a cold and dry lithosphere of the Zagros region

Simultaneous optical coherence tomography and scheimpflug imaging using the same incident light

For any single anterior chamber cross-sectional (tomographic) imaging method, there is a practical compromise between image size and image resolution. In order to obtain large field-of-view cross-sectional images of the whole anterior chamber and high-resolution cross-sectional images of the fine corneal layers, measurements by multiple devices are currently required. This paper presents a novel raster scanning tomographic imaging device that acquires simultaneous large field-of-view Scheimpflug (12.5 mm image depth, 50 µm axial resolution in air) and high-resolution spectral domain optical coherence tomography (SD-OCT) (2 mm image depth, 3.7µm axial resolution in air) using the same illuminating photons. For the novel raster scanning 3D Scheimpflug imaging, a tunable lens system together with numerical methods for correcting refraction distortion were used. To demonstrate the capability of simultaneous measurement of both fine corneal layers and whole anterior chambers topology, ex vivo measurements on 12 porcine and 12 bovine eyes were carried out. There is a reasonable agreement in the overall central corneal thicknesses (CCT) obtained from the simultaneous SD-OCT and Scheimpflug measurements. In addition, because the same infrared light beam was used to illuminate the sample, both OCT and Scheimpflug images were taken at the exact same location of a sample simultaneously in a single measurement. This provides a unique method for measuring both the thickness and the refractive index of a sample

The complete mitochondrial genome sequence of the Metschnikowia bicuspidata (Metschnikoff, 1884), an emerging pathogen of ‘milky disease’ in Chinese mitten crab

The outbreak of milky disease of Chinese mitten crab caused by M. bicuspidata seriously restricted the development of the crab industry. In this study, the mitochondrial genome sequence of M. bicuspidata was assembled, annotated, and further analyzed. The results indicated that the complete mitochondrial genome of M. bicuspidata was 75,095 bp, which contained two rRNAs, 23 tRNAs, and 13 protein-coding genes. The phylogenetic tree of 13 yeasts based on the complete mitochondrial genome was constructed which showed that M. bicuspidata (accession number OK514652) and M. bicuspidata (accession number MW147605.1) were clustered in a clade. To sum up, our research results would further provide essential data for the systematics and evolution study of M. bicuspidata

Preparation of polyprenol/poly (β-amino ester)/galactose targeted micelle carrier for enhancing cancer therapy

Lacking of substantial physiological activity and low utilization remains a problem for most conventional drug carriers. Polyprenol with beneficial medical effects and high availability could be an ideal candidate for solving this issue. Here, Ginkgo biloba leaves polyprenol (GBP)-based derivative was prepared by Michael addition reaction of poly (β-amino esters) (PBAE) with GBP and galactose (Gal). The intervention of poly (β-amino ester) and galactose promoted GBP-PBAE-Gal to depict as micellar carrier, enhancing the loading of hydrophobic DOX and the sensitivity to the specific tumor microenvironment, with the largest DOX loading of 28.62 ± 1.49 % and the efficient DOX release rate of 90.30 %. In the meantime, GBP-PBAE-Gal exhibited enhanced colloidal stability at 640-folds of dilution and in the presence of serum and realized the possibility of long-term storage at room temperature. Additionally, GBP-PBAE-Gal was safe for human red blood cells and human normal liver cells HL-7702. When applied for DOX delivery to HepG2 cells, GBP-PBAE-Gal increased the targeting of DOX to intensify its inhibition on HepG2 cells. Compared to free DOX, the DOX loaded into GBP-PBAE-Gal presented stronger anticancer activity, with IC50 of 0.56 μg/mL at 72 h. Besides, the anticancer mechanism study revealed that GBP-PBAE-Gal arrested the cell cycle in HepG2 cells, suggesting the potential of GBP-based carrier for intensive treatment. This research evidenced the feasibility and high availability of the GBP to use as a drug carrier, providing a novel candidate for drug delivery systems